Here’s what I was able to do last night:

• As I’ve mentioned, I know very very little about Arduinos or how to hook them up.  Although the Adafruit stepper motor page gives some guidance as to how to hook up the Stepper motor – 200 steps/rev, 12V 350mA, “Red, Yellow, skip ground, Green, Brown,” I have no idea which side or starting from which end of the terminal block this is supposed to go.  Admittedly, I have a 50/50 chance of wiring it up properly.
• I tried hooking up two old steppers I had scrapped from some old electronics – but all I got for my troubles was a small popping noise and the smell of electronics.  There was no blue smoke, no apparently burned parts, and I was able to program the Arduino Uno to blink and then run a servo through the Motor Shield.
• I designed and printed a spool for holding the monofilament line and which will fit snugly on the stepper motor shaft.  I got a little sidetracked playing with Skeinforge settings, but the spools turned out really well.
• I printed a gondola for holding the pen, designed for the Polargraph by John Abella
• I designed and printed a holder for the Arduino with the Motor Shield on it – but it was slightly too narrow for some reason.  I’ll have to redesign, reprint.
• I’ll have to design and print a new motor block as well as a filament line guide.  I have some cool ideas for the latter.
• I tried to use the Polargraph controller, but I wasn’t able to get it to do much.  I”ll give it another whirl tonight.
• I know I’ll also have to change some of the Polargraph Arduino code to accommodate the motor and spool combination I’m using.