Apple = asimov recent files + homemade collection (don't remember name)
macs only from me (really hard to find old ftps mainly)
Casio from many websites
Atari old nongood7800
Atarimania [You are not allowed to view links]
(7z packed files)
ST from atarimania (msa -> ST) and some good ftp about prgs
HP from HP 9845 website collector
hp museum other files
MSX have u tried to explore msx cds?
IBM winworld + various websites
Sinclair many new games (es SETO) + [You are not allowed to view links]
+ [You are not allowed to view links]
Japanese II x68000 torrent file.
These are only some hints, They'll not fill everything.