What is the coil resistance?
Do you know what is the permitted coil current?
The usual stepper drivers that are mentioned here (eg Sparkfun Easydriver) are probably intended for much larger motors. The Easydriver can supply up to 750mA. I have no idea what its minimum is.
My guess is something much more basic would be sufficient - maybe a ULN2003 would do the job (but don't rely on me for that).
How many motors will there be in your project?
...R