In Feb 2009 I did some research on a CNC, both homebuilt and kits. The feeling I get about homebuilts is that I don't have the mechanical skills or tools to get the slides, bearings and lead screws working smoothly. This leaves either a ready built without motors and electronics or a kit. I like the Fireball V90 by Probotix for $599 base.

24V 4.5A Switching Power Supply 100-240VAC 50-60Hz

A pretty powerful motor for the price is this model from Keling. 270 oz for $39.

 NEMA 23 	 4Wire Bipolar 	 1.8° 	 270 oz-in, 	 191 N-cm 	 ¼" w/ flat key 	 Dual Shaft 	 9A_KL23H276-28-4B 	 $39.99 	 Keling