Here's a decent place to look:
Any one of those motherboard CPU combos would do you good, but do a little research on it. Some are Micro-ATX which is smaller than your normal ATX Board. Usually it comes with 3 PCI slots opposed to 5. Try to get something with a 2400+ XP can't go wrong with those. Good chip and should do wonders for you. Look around for other CPU and Motherboard combo sales though. The only manufacturers they had at that site are chaintech, soyo, XFX , and Mach Speed....I've never had a motherboard from any of them so maybe someone else can give some heads up on that?