Hi,
You could try searching eBay for a second-hand Squirrel SCSI interface, or some other Amiga-specific CD-ROM and interface for the PCMCIA port...
Or, if you have a CompactFlash card, a cheapo CF-PCMCIA adaptor plus a CF card reader and a PC, it's easy enough to transfer it that way.
Another alternative is to take your Amiga's drive out and connect it to the PC, doing the transfer of OS3.9 files or even the full installation of OS3.9 from within WinUAE, but you will probably require an adaptor for that.
- Ali
