What hardware do you have right now? You might be able to reuse your RAM in a DDR400 setup. Same for your video card...
With AMD's price cuts, you may want to seriously consider an X2 3800+ 939 setup if you have good RAM you want to reuse (the only case in which you'd go 939 - otherwise the AM2 will cost the same and DDR2 will be cheaper.)
There are some ASRock 865 motherboards claiming conroe compatibility and will be DDR/DDR2, AGP/PCI-e16 so there's lots of inexpensive options, evn if they're not the BEST overclockers (save you a hundred bucks though!)
With AMD's price cuts, you may want to seriously consider an X2 3800+ 939 setup if you have good RAM you want to reuse (the only case in which you'd go 939 - otherwise the AM2 will cost the same and DDR2 will be cheaper.)
There are some ASRock 865 motherboards claiming conroe compatibility and will be DDR/DDR2, AGP/PCI-e16 so there's lots of inexpensive options, evn if they're not the BEST overclockers (save you a hundred bucks though!)