I just bought my new parts from Newegg for $725 shipped and $50 in rebates that bring the final cost to $675.
CASE: Antec 300
PSU: Antec 650 Earthwatts
Motherboard: Asus P5Q Pro
CPU: E8400 There was a $45 combo deal with the MB
RAM: 2x2GB Mushkin 5-4-4-12 Lat 5 1.8v DDR2 800
DVD Burner: Liteon SATA
HD: 500GB 7200 32MB cache Seagate SATA
Case Fans: 4 pack of Cool master
Video: Gigabyte HD 4850 1GB Core Clock 700 with Zalman cooling
My goal was to shoot for $600 but I wanted the better processor and video card.
I'm moving up from my Athlon XP3200+ with a x850 Pro 256MB video.