ok, this is the schematic for the motor driver circuit I'm using:
The only thing that is not in my circuit is the switch. Also, I am not using 12v, as the motor is only 3v I am doing it all using 5v so the "To Motor Power Supply" goes to +5v
Here is a Schematic for the amplifier sub-circuit I am using:
The "To Arduino Analog 0" goes to Analog 0 and is used to set the delay time in the code.
Here is a photo of the circuit:
( just in case you want to see larger images:
http://www.flickr.com/photo_zoom.gne?id=480335547&size=l
http://www.flickr.com/photo_zoom.gne?id=480335533&size=l )