A number of years ago I found someone's online fan site in which they had expanded the adventure Squaring the Circle (from Hellbound) by including, among other things, a trip down to the "Seventh Sphere Of Carceri", I think it was. I was looking for it recently, but can't find it anywhere -- and indeed, the one link I found to the page indicates that it's no longer at that location. Does anyone know where it has moved to or, failing that, did anyone happen to download it?
[FYI, the reference to PSLost's augmentation was at Zimriel's page. Can't find any trace of it anywhere else.]
It used to be accessible from Planescape Pieces, but none of the links work anymore.
Eric Noah did an expansion to "Field of Nettles," though: http://webpages.charter.net/ericnoah/noahrpg/d_and_d.htm