I have an Intel Lancewood L440GX, which I initially used with PII-450mhz/2mb Xeons. I found one on ebay
here. This is the exact same one that I have and it's got everything onboard - video, LAN, LVD and UW SCSI, etc. Highly recommended. You will need mounting brackets for your processor cartridges. This guy isn't selling anything but the board so keep that in mind. I bought mine new in a retail box for $350 (ouch!) and it came with them. You will also need a pair of VRMs....but I am selling a pair that will work for you for $20 for both! (hint, hint) You'll probably want the custom ATX I/O shield that Intel makes to go with this because it's onboard video and LAN won't fit in a normal ATX I/O shield. This also comes in the retail box. Otherwise these VRMs can be found on ebay for about $20 each. I got my motherboard from
Centrix International. They're located in Texas. They also sell OEM bare boards and stuff like ATX I/O shields seperately.