Arduino shields, stepper drivers and software

Arduino CNC Shield

http://blog.protoneer.co.nz/arduino-cnc-shield/

A4988 Stepper Driver

https://www.pololu.com/product/1182

GRBL

https://github.com/grbl/grbl/wiki/_pages

ChiliPeppr

http://chilipeppr.com/grbl

Universal-G-Code-Sender

http://www.shapeoko.com/wiki/index.php/Universal-G-Code-Sender