i dont think you can buy them from just anywhere. you need to make them or have someone make them for you. if you REALLY want to know more about it and like electronics projects, i might be able to point you in the right direction..
ok, the plugins seem to have been renamed and had some text added to the first few bytes eg. '??? Support for PSX2 Emu', where ??? is CD, mouse, sound etc...
cd.dll appears to be tsgmscd.dll
mouse.dll appears to be padDudDIMouse.dll
keyboard.dll appears to be padDudDIKeys.dll
gamepad.dll appears to be a plugin written by Smartazz
sound.dll appears to be spuKazDSound.dll
d3d.dll appears to be gpuPeteD3D.dll
soft.dll appears to be gpuSoft.dll
plus also a bios file which is 698Kb which is a pretty wierd size ???