where to get FREE CNC software (for XP)?

hey, I'm building a 3-axis CNC milling machine. right now I'm looking for a FREE ( or VERY CHEAP) CNC software...
I would like something "common" since that'll be the easiest for getting help later on...
I'm thinking of MACH3 (since that's what I've seen that diy'ers use mostly)
anyone knows where to get it?

(I'm using XP, because I've got a computer for free, since my usual computer is a laptop and doesn't have a parrallel port, and i wish to use a computer ONLY for CNC)

Try to visit this source it may help you to get the free CNC software http://www.hobbycncsoftware.com/taxonomy/term/721
linux cnc