Linear Motion Parts Source for Hobbyists ?

I would like to build a moderately priced cnc router to make balsa model
airplane ribs. I would like to find a source that sells linear motion
products (ball screws, rack and pinion, timing belt etc.) to hobbyists
preferably with online ordering. I would also like to hear feedback on
stepper motor controllers and software (I've downloaded the "Master 5 CNC"
demo and have been looking at the "Hobby CNC 3 axis CNC Package" at
http://hometown.aol.com/drigotti/pages/package.htm )

Any feedback or suggestions would be much appreciated.
Thanks