I ended up getting a used Asrock Dual939 for $45 shipped. It can be upgraded, supposedly, to AM2 socket with an adapter and has both AGP and PCIe slots, which works great for this build as it will double as a -*test*-('")ing platform. Using a Coolermaster case I have lying around, a PC P&C silencer 360 I use in my business for -*test*-('")ing and a 7300GT. 2 sticks of PC3200 RAM for 1Gb of memory and an old 80GB SATA drive. Had to but a DVD RW, floppy drive and a copy of XP though.

Plenty of rig for a two year old but I'll use it in my business as well.