This is the breakout board that i am looking at using:
http://www.ebay.com/itm/MACH3-5-Axis-CNC-Breakout-Interface-Board-for-Stepper-Motor-Driver-CNC-Mill-/271059157869?pt=LH_DefaultDomain_0&hash=item3f1c62836d
Well setting the pin modes and levels should be an easy learn. What would you keep in mind when connecting an Arduino to an external board?