Hello I'm in the process of designing/building a 4' x 8' 5 axis CNC router. I ran in to a problem. I was going to use an Acme threaded rod for the X axis but I heard of problems with such a long span. So I was thinking of using timing belts. Now the problem is, I can't find a place that sells them "cheap" and shows the price. Any ideas? Thanks

Stock Drive Products and McMaster-Carr, google will get your there, direct on-line ordering.

Thanks thats exactly what I was looking for, I can't believe that I missed the first one when I did a search. But anyways Thanks.

Have you thought of using a Rack gear and pinion?
http://www.smallparts.com/products/descriptions/grs.cfm