dave.. looks good..
bit of a pain getting the phase sequence for motors though.. but i'm sure u should be able to get it for the one u'r using. Actually.. i think i might have a couple spare steppers in my junk box at home that u could use.. but u'd have to find out all the details.
So you'd probably got from the USB controller out to a darlington(uln 2003) array then to the motor coils. Definately doable.
el
