Lead Screws...where do you get them???

I'm sure this question has been asked...I've looked through some of
the archives, but haven't found much..

I set out not long ago to build a CNC router...roughly 2' x 2' XY
and 3-6" Z.

I've come to find that the difficult and expensive items are the
lead screws & some sort of slides.

Can anyone provide a source for new/used ball screw/ lead screws at
an affordable price. (I've been regularly checking ebay, with no
luck)

I know that the 1st question people will ask is what accuracy I'm
looking for. I'm not sure...I want to be able to route peoples
names & graphics into wood.

I've purchased the controller & steppers
(http://209.41.165.153/stepper/FETcruiser.htm) and just need to find
the lead screws & linear slides.

I'm still looking for a source for linear slides..I'm currently
thinking about these THK slides...
(http://cgi.ebay.com/ws/eBayISAPI.dll?
ViewItem&item=2581747566&category=55826&rd=1)

Anyone have an opinion??

Thanks a bunch to anyone who can give me some guidance etc.

Wade Conner