Marty,
You've got a 2A power supply and a 4A/phase stepper... at best your stepper is going to be severely curtailed on its torque to about 100ozin because you'll be limited to 1.5A/phase, but that might be OK for your application.
Well I'll admit that board was cheap at $12 or so, but then you get what you pay for! I can't recommend a single axis stepper ready made but there are a couple on ebay using the Toshiba chip sets. We have a couple of good suppliers in the UK of locally manufactured boards but I don't know if thats viable for you.
If you're in Europe why not come and visit the UK CNC Community at http://www.mycncuk.com