Heres what i got:
Budget: 800$ max would like 700$
When do i plan on getting it: Mid-August or Later

This what i found so far at a price tag of 665.37$

Barebone Kit:
Soyo Case
ECS N2U400- A Nvidia Socket A Atx Motherboard
Amd Sempron 2800+ Socket A Processor
Ultra Copper Base Cooling Fan up to Xp 3000+
Ultra 512mb PC3200 DDR400MHZ Memory
Soyo Ps/2 Silver and Black Multimedia Keyboard
Ps/2 And Usb Mouse(Black)
Soyo 400Watt Power Supply
Price Tag: 199.99

Seperate:
Video Card- XFX GeForce FX5500/ 256mb DDR/ AGP 8x/ VGA/ DVI/ TV Out
60.00
-My current card is Geforce 4 Ti4200 128 mb

Hard Drive:
Seagate/160 GB/ 7200 Rpm/ 8mb Buffer/ ATA-100/ EIDE/ Hardrive(retail package)
130.00- 99.00 after rebates

Shipping and Handling X Equipment
= 665.37 w/o Rebates

I don't understand your math, I get $390 from the stuff you list below, unless you forgot to list something.

Do you include xp in the price? How about a monitor and key/mouse, are they needed in that price as well?

Here's a rig, I recommended not too long ago. It's all from tigerdirect, but if you look around you'll get the stuff cheaper at other places, like newegg, zzf, etc.

Mobo: $89.99
http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=1366536&CatId=1569

Cpu: $147.99
http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=1366603&Tab=2&NoMapp=0

Ram: $91.99
http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=669365&Tab=2&NoMapp=0

Video: $179.99(-$30) (since it's a pci-e mobo, you'd need pci-e cards)
http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=1351110&CatId=0
-OR-
Video: $234.99
http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=1229514&CatId=0

Case: $49.99
http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=935378&CatId=0

PSU: $64.99
http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=1407918&CatId=0

Total:$627-682

ecs makes a pretty crappy product, excepting thier not-too-bad k7s5a pro

go with a better motherobard, and a better power supply (raidmax, thermaltake, or antec). i recommend the gigabyte ga-7n400 pro, from experience.