I'm thinking about building a new computer, alas, I'm not nearly as well versed in some of the newer hardware stuff. Anyone have some good advice on motherboards and processors? Price range is about $300 or so for both of 'em.

You might be able to score a AMD 64 3200 winchester socket 939 and a MSI K8N Neo4 for that if you shop around. Try Ebay. That has the N-Force 4 chipset with a PCI express slot for graphics or try an Asus A8V Deluxe if you have a decent AGP card you want to use still. It has a VIA chipset but it runs nicely. Lots of bells and whistles and since its considered out of date...its a good cheapo board.