Desperate times call for desperate measures. I'm sorry guys, but i'm giving you the best bang for the buck, and i think you need a socket 939 and pci-e motherboard. WHat i'm willing to cut down for now is gfx card, to meet your budget.
ASPIRE X-Dreamer II ATXB4KLW-BK Black Steel ATX Mid Tower Computer Case 420W Power Supply-56
AMD Athlon 64 3000+ Venice Socket 939 Processor-146
Arctic SIlver Premium Photosynthetic Silver Thermal Compound Arctic Silver 5-8
CHAINTECH VNF4/Ultra Socket 939 NVIDIA nForce4 Ultra ATX AMD Motherboard-85
CORSAIR ValueSelect 1GB (2 x 512MB) 184-Pin DDR SDRAM DDR 400 (PC 3200) Unbuffered Dual Channel Kit System Memory Model VS1GBKIT400-79
Seagate Barracuda 7200.7 ST380817AS 80GB 7200 RPM Serial ATA150 Hard Drive-62
ASUS EAX300SE/T/128 Radeon X300SE 128MB DDR PCI Express x16 Video Card-58
NEC Black IDE DVD Burner Model ND-3540A-56
Windows XP Home Edition w/SP2-92 (Do you need?)
Total $550. As for shipping, depending on where you live, i believe newegg has free shipping. As for tax, i dk. I live in HI and i would have to pay shipping and tax. Tax for me would be $24 for that build. As for shipping $$$... If you have no clue what Arctic silver is, get rid of it, you don't need it. $8 is alot for such a small budget.
Roger