Dont bother with a floppy drive.
Buy a 44-pin IDE to CF adapter and a CF card to use as a hard drive. You'd pick them both up very cheaply.
You can use your PC and WinUAE to install Workbench, WHDload, games etc. onto the CF card before putting into the A600.
If you dont want to cut your A600 case (so you can easily get the CF card in and out) consider ALSO getting a PCMCIA to CF adapter and a second smaller CF card for transferring data to and from the PC. You'll need the driver CFD and FAT95 program installed, both are free on Aminet.
If you REALLY want a disk drive, you can modify a Panasonic U257
http://www.carrott.org/amiga/floppy.html
