My latest post before this one in the Log X thread is a listing of the Prime Material worlds canonically known to exist (as opposed to the standing invitation to add your own Primes for planeswalkers to visit). I would welcome any additions to the list.
I particularly expect that quite a few would be listed in the Spelljammer setting, which I don't have, and possibly a number of them in various Dragon Magazine articles.
Though quite a few events and items of interest are associated with "an unknown prime," I would prefer to avoid these in the list, seeking worlds that have at least a little development. A name, even if it was given by planeswalkers, would be needed, unless there was a very good reason to list "unnamed Prime world." The source in which it is found would also be appreciated.
Paul Westermeyer's Guide to the Spheres (PDF link) was useful in assembling this, and I recommend you check it out for more complete information.
Abeir
World parallel to Toril, separated from it long ago by Ao in order to end the war between the primordials and the gods.
Aebrynis
Cerilia: Birthright Campaign Setting.
Aduria: The continent where most of Cerilia's humans came from originally.
Aelos
CM6: Where Chaos Reigns
Aerofalyn
Elvish garden world. The Maelstrom's Eye, 39. Destroyed by goblinoids.
Alabeth
Practical Planetology, 33
Alpha Centauri
Mentioned in the Immortals boxed set. The closest star to Mystara.
Anandia
Wasteworld ruled by halflings and umber hulks. Spelljammer, Realmspace.
Arborianna
Evermeet: Island of the Elves, page 87. Gold elf world conquered by scro.
Arda and the Lost World
From Ray Winninger's Dungeoncraft in Dragon Magazine. http://www.darkshire.net/jhkim/rpg/dnd/dungeoncraft/
Armistice
Practical Planetology, 10
Astrylon
Spelljammer comic #10. Probably in Pathspace.
Atalya
A lost continent. "Lost Empires." Dragon #214.
Athas
Dark Sun campaign setting.
Azeroth
Warcraft RPG.
Barbuda
Practical Planetology, 30
Barovia
Strahd von Zorovich's homeland on an unknown world. See RM1 Roots of Evil.
Barrara
Spelljammer comic book #10. Same sphere as Astrylon.
Barsoom
E.R. Burroughs' science-fantasy version of Mars. Warriors of Mars, D&D White Box.
Bas Lag
The world of China Mieville's Perdido Street Station. Dragon #352.
The Black Fen
Mentioned in Q1.
Bodi
Practical Planetology, 16. Forest world.
Bondel
The Radiant Dragon, 285. Elven world, population murdered by scro.
Borka
Smashed orc world. Spelljammer, Greyspace.
Boroda
Jungle planet. Spelljammer comic #5-8.
Bustlum
Gnomish world. TSR Trading card #208, "Grazzle."
C'T'lk'atatspace
Dominated by jade green insects. TCMC6 The Ultimate Helm pg.7
Kingdom of Caer Sidi
Q1: Queen of the Demonweb Pits, Fiendish Codex I, Expedition to the Demonweb Pits. Possibly located on Ginsel in Greyspace.
Casaspace
Contains Rock of Bral, Spiral, Ironpiece, Numliador, Minial’s Arch. Sources: Hackjammer, The Maelstrom's Eye by Roger E. Moore.
Chanak
Creative Campaigning, 32
Chandos
Water world with thick "crust" of floating earth bodies. Humans, orcs, and dwarves. Spelljammer, Realmspace.
Charon
Practical Planetology, 27
Chislev
Stormy jungle world. Spelljammer, Krynnspace.
Citadel of the Keepers of the Flame
Asteroid. Spelljammer comic #14-15
Clusterspace
The Astromundi Cluster
Collar
Gas giant inhabited by lizardfolk, aaracokra, and dragons. Spelljammer, Realmspace.
Compendium
A planet or crystal sphere, location unknown. The base of the spelljamming scholars known as the Seekers. The Complete Spacefarer's Handbook, page 93.
Comporellon
Practical Planetology, 4
Conatha
Elliptical water world. Spelljammer, Greyspace.
Damocles
A world in Mystara's solar system, doomed to be destroyed. Immortals boxed set. I'm leaving out the other planets in the system, since they're entirely undetailed and don't have "official" names.
Dark Continent
A continent based on Africa. Dragon #189.
Darkspace
Possibly related to the Polyhedron #114 world? SJA3 pg. 39
Darnannonspace
Dungeon #36 pg. 41
Dawnrise
TSR Trading Card #318 ‘Hajallian Thremintha.' Elven world exterminated by scro.
The Dead Shell
SJA2 Skulls & Crossbones pg.46
Dohwar homeworld
MC9. Homeworld of the penguin-like dohwar.
Doth B
The Maelstrom's Eye, 54. Contains a library.
Dragon Overlord World
The original planet where Krynn's Dragon Overlords came from. Age of Mortals, War of Souls, etc.
Dragonrealm
Dungeon #10. A world where extra-strength dragons are the dominant race. Humans are considered a myth. Another portal in this adventure leads to an unnamed desert world. Possibly the Dragon Overlord World?
Dukagsh
Scro homeworld. Dragon Annual #1.
Dunador
Destiny of Kings.
Earth
Ancient Greece: Age of Heroes Campaign Sourcebook, Deities & Demigods, Legends & Lore.
Ancient Rome: The Glory of Rome Campaign Sourcebook, Dragon #133
Averoigne: X2 Castle Amber
Celtic Ireland: Creative Campaigning, 18; Celts Campaign Sourcebook, Legends & Lore
Age of Vikings: Vikings Campaign Sourcebook, Dragon #90.
Dark Age Britain: Dragon #257, Dragon #263
Dark Age France: Charlemagne's Paladins Sourcebook
Dark Age Russia: Dragon #290.
King Arthur's England: Deities & Demigods, Legends & Lore
Outremer: The Crusades Campaign Sourcebook, the novel Black Crusade by Ari Marmell.
The Cavalier Age: A Mighty Fortress Campaign Sourcebook
Gothic Victorian era: Masque of the Red Death setting
Mesopotamia: Creative Campaigning, 21, Deities & Demigods 1st edition, Dragon #16, Dragon #329
Africa: Creative Campaigning, 23; Dragon Magazine #189, Dragon #215, Dragon #122, Dragon #116, Dragon #195, Dragon #202, Dragon #209, #27
Hyperborian Earth: The deities of Robert E. Howard's Hyperborian Earth were described in Gods, Demigods, and Heroes, and TSR published a Conan roleplaying game. Adventures taking place in this realm include Conan the Buccaneer, Conan the Mercenary, Conan Triumphant, and Red Sonja Unconquered.
India: Dragon #189. Dragon #225.
Robin Hood: Dragon #274
The Young Kingdoms: Deities known to the Earth of Elric of Melnibone appeared in the original printing of Deities & Demigods.
Lovecraftian Earth: Deities & Demigods (1st edition), d20 Call of Cthulhu
The Future: Gamma World, Stardrive, Metamorphosis Alpha, Star Frontiers, Dark Matter, Top Secret, d20 Modern, etc.
Eberron
Eberron campaign setting. Continents: Khorvaire, Aerenal, Xen'drik, Frostfell, Sarlona, Argonnessan.
Eloysia
A universe where worlds are bubbles of air in a vast expanse of solid matter known as plenum. Eloysia is also specifically the name of a bubble in this universe where the island nations of Trann and Volde float in the air in the outermost shell of islands around the central sun. From module M5, Five Coins For a Kingdom. Similar to Kofuspace.
Epsilon Eridani
Mentioned in the Immortals boxed set. The magically-capable civilization nearest to Mystara.
Esfah
Dragon Dice world. Lava elves and such. Dwarves and coral elves (good guys, serving Nature) and goblins and lava elves (bad guys, serving Death). Novels: Cast of Fate by Allen Varney and Army of the Dead by Edo van Belkom
The Fallen Lands
The default 4e world. Also known as "Points of Light" or the Forgotten Kingdoms, or simply the World. Home of the fallen empires of Arkhosia, Bael Turath, and Nerath, and current home of Nentir Vale.
Falx
Illithid planet. Practical Planetology, 7
Faeriespace
SJA3 Crystal Spheres pg. 18-27
The Frozen Lands
Q1 Demon Queen of Spiders, Queen of Spiders supermodule. Possibly the same as the Iron Wastes, Kostchchie's realm in the Abyss.
Fungo
Concordance of Arcane Space, 77
Gallamede
From Fiendish Codex I: The Lost Entries. Warriors and clerics from this world invaded the Abyss nearly a decade ago. Possibly also the source of the "fantastic cityscape of human design that appears to have been abandoned a thousand years ago on Abyss layer #628 - this might also be Suel.
Garden
Tree world, also called Yggdrasil's Child. A cluster of asteroids linked by a planet-sized tree, sharing a common atmosphere. Spelljammer, Realmspace.
Garrash
Practical Planetology, 22
Ghenrek IV
The Wilderlands of High Fantasy. Also known as Gaia to some of its inhabitants. Rhadamanthia is the most well-known continent.
Ginsel
Crescent-shaped world. predominantly humans, with some demihumans. Ginsel is a Machiavellian society known for its sharp merchants and nasty politics. Possibly the home of the Kingdom of Caer Sidi (Q1, FC1, Expedition to the Demonweb Pits). Spelljammer, Greyspace.
Glemayne
Homeworld of the voadkyn Ombidias. Factol's Manifesto.
Glowrings Sphere
TCMC3 The Maelstom's Eye pg. 33
Glyth
Mind flayer world. Spelljammer, Realmspace.
Golotspace
SJA4 pg. 52
Gorthspace
SJA4 pg. 52
Gnibile
Undead world. Gas giant. Gnibile has many portals to the negative elemental plane, and the quasi elemental planes. Spelljammer, Greyspace.
The Great Ocean
Mentioned in Q1.
Greatspace
SJA3 Crystal Spheres, 30-32
Greela
Cluster world. Predominately humans and elves, smattering of other demihuman races, few non-evil giants and giantkin. Spelljammer, Greyspace.
Guldor
Fiendish Codex I: Hordes of the Abyss, Q1: Queen of the Demonweb Pits; Probably the location of Truegard, from Expedition to the Demonweb Pits. Definitely the location of the kingdom of Maldev from Q1.
Gwynedd
Home of the Deryni. Dragon #78.
H'Catha
Disk-shaped water world with a single mountain in the center, called the Spindle. Inhabited mainly by beholders. Spelljammer, Realmspace.
Heartspace
TCMC5 The Broken Sphere pg. 16-106
Herdspace
Crystal sphere set up like a dyson sphere. Megafauna live on the inside of the shell. TCMC3 The Maelstrom's Eye pg. 49, 168+
Herospace
SJA3 Crystal Spheres, p. 9-17. Complete Spacefarer's Handbook, pages 85 and 87.
Ignia
Practical Planetology, 20
Ind
PSMC1, 30, 34, 66
Insectare homworld
Mountainous, forested. MC9.
Io's Blood Archipelago
Council of Wyrms campaign setting
Izmer
The setting of the D&D movie.
Jakandor
Isle of War, Isle of Destiny, Isle of Legend.
Labyrinth of Arachne
From Q1. Possibly located beneath Celene/Kule, one of Oerth's moons.
World of the Lost Ones
Homeworld of the clockwork horrors. MC7 Monstrous Compendium Spelljammer Appendix. Dragon #350, page 59. Possibly in Lostspace (see below).
Ka'jk'z
The neogi homeworld. Possibly destroyed by clockwork horrors. Dragon #214, p. 58, and Dragon #350, page 59.
Kaddas
An ancient empire. Its capital is Kaddastrei. The city of Blackwall was once part of it. From Cityscape.
Karawenn
From the First Quest novels. Possibly on Mystara.
Karpri
Water world. Spelljammer, Realmspace.
Kellinon
A Material Planar nation, Well of Worlds
Knell
A Material Planar nation, PSMC3, 108
Kofuspace
A solid crystal sphere filled with bubbles. SJA4 Under the Dark Fist pg. 52. Similar to Eloysia.
Korvspace
Sphere of the elvish Korvadan Empire. Polyhedron #81
Kra'akenspace
Air-filled sphere of floating islands. SJA4 Under the Dark Fist 52
Kreenspace
Thri-Kreen of Athas, p. 84.
Krynn
Taladas: Time of the Dragon boxed set
Ansalon: Dragonlance campaign setting
Otherlands: Otherlands campaign expansion
Adlatum: http://www.dlnexus.com/adlatum/ (fanon)
Kule
Also called Celene and the Handmaiden. Spelljammer, Greyspace. Polyhedron #113.
Lirak's Cube
The Maelstrom's Eye, 54. Complete Spacefarer's Handbook, 78.
Logicus
Mechanical world of dabus and modrons. From Doors to the Unknown.
Lolth's Prison - Q1
Lorpulanspace
TCMC6 The Ultimate Helm pg.7
Lostspace
Ruined sphere. SJA4 Under the Dark Fist pg. 52. See also World of the Lost Ones, above.
Lurienia
The Complete Spacefarer's Handbook, 121, Elven fortress world.
Mahasarpa
James Wyatt's Indian-themed campaign setting. http://www.wizards.com/default.asp?x=dnd/we/20011019a
Malena
An "extra-dimensional world," the primary setting of Module CN2 Conan the Mercenary. A kingdom of light and goodness invaded by the King of Demons, Yama.
Manifest
The city of the ghostly dead in the Ghostwalk campaign setting. Surrounded by various countries: Bazareene, Salkiria, etc.
Matera
Mystara's visible moon. Wrath of the Immortals. I11 Needle.
Masg
Dragon #244. Home of the Masgai. Capital city called Rig-Veda.
Moragspace
Scro-dominated sphere. The planets have been devoured by gammaroids. SJS1 Goblins' Return pg.7, SJQ1 Heart of the Enemy pg.81
Mystara
Known World: D&D Gazetteer Series
Savage Coast: Savage Coast Campaign Setting
Hollow World: Hollow World Campaign Setting
Blackmoor: Dave Arneson's Blackmoor Campaign Setting (set 4000 BC)
Thunder Rift
Ghyr
Nehwon
Lankhmar campaign setting, based on Fritz Lieber's books. Deities & Demigods, Legends & Lore, Lankhmar softcover, etc.
Neirston
Dead Gods, 12. Portal key = beauty.
Nexspace
TCMC5 The Broken Sphere pgs.90-91, 139
Nightlock
The original planet where the drow that settled on Krynn came from. (2nd edition Dragonlance Wild Elves supplement).
Nightworld of Vlad Tolenkov - Q1
Nivil
Practical Planetology, 40
Nubis
Practical Planetology, 37
Oerth
Flanaess: World of Greyhawk campaign setting, From the Ashes, The Adventure Begins, Living Greyhawk Gazetteer
Sundered Empire: Described in the Chainmail Miniatures Game, and Dragon #286-294.
Hepmonaland: The Scarlet Brotherhood
Amedio Jungle: The Scarlet Brotherhood
Fireland: Dragon Annual #1
Celestial Imperium: Dragon Annual #1
New Empyrea: Frank Mentzer's Aquaria campaign, detailed in RPGA modules R1-R4, and the Egg of the Phoenix supermodule.
Old Alphatia (The Star Kingdoms)
The homeworld of the Alphatian people from Mystara. Mentioned in the Dawn of the Emperors boxed set, Wrath of the Immortals, and in adventure M1: Into the Maelstrom
Ortho
Harmonium homeworld. From The Factol's Manifesto.
Ouiyanspace
The birthplace of The Spelljammer. Also known as The Broken Sphere. TCMC6 The Ultimate Helm pg.246+
Pangaea
Magic Encyclopedia, Volume One, page 8, 12, 13. The world where the wizard Prismal the Outrageous was born. Contains two named cities: Electropolis and Chamshaea, on opposite sides of the planet.
Passarspace
SJA4 Under the Dark Fist pg.52
Patera
Mystara's invisible moon. Also called Myoshima. Princess Ark series, Champions of Mystara.
Pathspace
Sphere of the planet Devis. TCMC2 Into the Void pg.10
The Pearls
The Broken Sphere, 308. A constellation of six unnamed crystal spheres.
Pelinore
A D&D campaign world from Imagine Magazine, the official periodical of TSR UK. Pelinore is a flat world that grows toward extreme alignments near the edge and perfect balance in the center. Beyond the edge is a void of nothingness, from which the gods arrived. Pelinore includes the sprawling, multicultural City League.
Pellham
From module C4, To Find a King, and C5, The Bane of Llywelyn. Worships the Celtic pantheon.
Penumbra
Artificial flatworld that surrounds a sun. Created by the illithids during the heyday of their empire. Detailed in Dawn of the Overmind by Bruce R. Cordell. Located in the sphere of Truespace.
Lands of the People
A continent based on North America. Dragon #205.
Parcelius
Into the Void, 200.
Plata
Practical Planetology 46
Pirtelspace
Dungeon #36, 45
Polyhedron #114 world
"A World of Your Own" by Roger E. Moore. I have no idea what the proper name of this is. Possibly in Darkspace? It's a world where the sun died, inhabited by berserk elves, living vampires, and necromancy run rampant.
Primespace
TCMC5 The Broken Sphere pg.202
Psurlon homeworld
Dark Sun MC II, p. 82. Now destroyed.
Purity
Homeworld of the Xenos, an organization of human supremacists. The Complete Spacefarer's Handbook, 95.
Pyrespace
Pyrespace is based on the solar system presented in the Shadow of the Spider Moon article from Polyhedron #151/ Dungeon #92. AKA Spiderspace.
Radole
Practical Planetology, 13
The Realm
The home of the D&D cartoon show.
Redeye space
SJR1 Lost Ships pg.62
Refuge
Mercane world. "Rough Times on Refuge," Dragon Magazine #159, page 10
Raenei
Oerth's second moon. Also called Luna and the Mistress. Spelljammer, Greyspace. Return of the Eight.
Ranais
Dead Gods, page 52
World of the Red Forest
The locals worship Elishar, from 3e Deities & Demigods. The trees have red to orange trunks, purple or black leaves with silvery undersides. Described in Expedition to the Demonweb Pits; the world is currently being invaded by the forces of Lolth.
Reorx
World of mountains and chasms, inhabited by dwarves and gnomes. Spelljammer, Krynnspace
Rokugan
3rd edition Oriental Adventures. Also on this world are the realms of the Burning Sands and Ivory Kingdoms.
Rublia.
Uncaged: 120. Skeartim is a greater power there. Zadara the titan was once worshipped there.
The Factol's Manifesto, 83. Wemics Lethea & Lesander are from there. They were captured by the biologist Gorad Drummerhaven and brought to Sigil.
Salzarspace
SJA4 Under the Dark Fist pg.53
Sazaurspace
SJA1 Wildspace pg.3
Sea of Shadows
Lost Ships, 34.
Shadowspace
SJQ1 Heart of the Enemy pg.31
Shannara
Based on the Terry Brooks novels. Dragon #286.
Sirion
Fire world in Krynnspace. Spelljammer, Krynnspace
The Spectre
The Spectre, a flatworld. Spelljammer, Greyspace.
Spider Ship Garage - Q1
Spiral Desert
Invaded by Lolth, surface-dwelling drow, and giant trapdoor spiders. The drow keep humans, kobolds, and thri-kreen as slaves. Expedition to the Demonweb Pits
Ssirik Akuar
Illithid planet. Dragon #150, "The Sunset World."
Steel Star Space
SJR1 Lost Ships pg.56
Talangran
Dungeon #34.
Talaron
Homeworld of the Talaire. Complete Psion, Dragon #281. Destroyed by illithids.
Tékumel
The Empire of the Petal Throne RPG first published by TSR in 1975. Not technically D&D, but whatever. It used the same rules initially, from what I understand.
Tellene
The Kingdoms of Kalamar campaign setting.
Thalassa
Practical Planetology, 25
Thasiaspace
SJA4 Under the Dark Fist pg.53
Threnody
Kiaransalee's (destroyed) home world. Demihuman Deities
Tir
Dragon #244. Home to the Fainil and the Telvar. Perhaps also the home of the Xakhun drow clan.
Toril
Maztica - Maztica campaign setting
Zakhara - Al-Qadim campaign setting
Hordelands - The Horde boxed set
Shining South: A 3e hardcover
Unapproachable East: A 3e hardcover
Faerun - The Forgotten Realms campaign setting
Malatra - RPGA Living Jungle campaign
Evermeet: Evermeet sourcebook
Kara-Tur: Kara-Tur boxed set
Returned Abeir: 4th edition Forgotten Realms
Torus
Practical Planetology, 44
Troulos
A flatworld. From Legend of the Spelljammer, page 8.
Truegard
A dwarven empire that spans a continent; mentioned in Expedition to the Demonweb Pits. Probably located on the world of Guldor.
Tuimuhva
Tales From the Infinite Staircase, page 19. Contains the metropolis of Gunthis.
Uerth
A reverse-alignment mirror version of Oerth. [i]Expedition to the Ruins of Greyhawk[/b]. Other versions of Oerth include Yarth, Earth, and Aerth.
Unipaxala
"The Peace Asteroid." TSR Worlds Annual #1, Spelljammer comic #3-4
Verdorth
Druid world. PSMC3, page 96
Vergonspace
SJA4 Under the Dark Fist pg.53
Vistaspace
Garrash planet
TCMC5 The Broken Sphere pg.201, 213, SJR4 pg.22
Vodonispace
SJA4 Under the Dark Fist pg.51
Vodonika
SJA4 Under the Dark Fist pg.53
Wayspace
TCMC2 Into the Void pg.186
Westeros
The setting of George R.R. Martin's "A Song of Ice and Fire." Dragon #305.
Winterspace
Sphere of the planets Armistice and Radole.
The Cloakmaster Cycle: The Radiant Dragon pg.24-30, 49. SJR4 pgs.10, 13
Wheel of Time
The Wheel of Time Roleplaying Game, The Prophesies of the Dragon
Zalanispace
SJA4 Under the Dark Fist pg.53
Zivilyn
Accursed gaseous world. Spelljammer, Krynnspace. 12 moons.
Zphidnin
The Maelstrom's Eye, 54.