A friend of mine got a C128 and I want to make a
drive emulator
 for him. I wasn't able to find anything suitable (e.g.: Runs in
 windows or linux, preferable windows, has schematics avaiable, free)
 in google. Anyone can help? :o) 
 Are you looking for hardware or software?  I
really like Jim Brain's
 uIEC, and it's fairly inexpensive.  Hands down the single best piece
 of hardware I've ever purchased for my C-64! 
 
    I'm pretty sure it is! But I'm a bit "too far away" and short on
 money :P So I'll have to find a locally reproductible option :)