The idea of powering on platforms Arduino is common, and for this you will need a bridge driver as the paddle below. For those not familiar with the Arduino, It is a label of prototyping and development with open source. Very interesting, Read more in this article.
The Board is based on the chip L298N and allows you to connect two motors (OUT1 and OUT2 in green). It also has four digital inputs (PWM can) to connect the two motors in both directions possible.
The plate comes with metallic spacer.
Detail of chip L298N, in your sink.
The input voltage can be taller than the digital input, coming up to 35V. The current supports peak 2A. I did use, a cart with Bluetooth control, She doesn't worry! I leave the link to the product:
http://www.dx.com/pt/p/l298n-stepper-motor-driver-controller-board-module-143633