For $1000 you should be able to build an outstanding computer!
Here's a few sites to check out for parts and or complete/barebones systems:
http://www.tigerdirect.com
http://www.newegg.com
I would buy a barebones system from tigerdirect. It'll be shipped with a case, floppy drive, power supply & motherboard (depending which of the many setups you can choose from). This will run anywhere from $150-$500 depending on which model you choose. Some of the kits actually come with the whole 9 yards! The parts all come in one box and you'll need to assemble yourself.
This is what I would buy seperately:
512Mb memory minimum
Video card (preferably 8x AGP)
Hard drive (great deals for drives between 80Gb and 120Gb)
Sound card (I don't like built in, I would get a soundblaster)
Monitor (You can get great deals across the net)
CD/RW - Dirt cheap, you can get a 52x writer for less than $50)
DVD writer - Again, dirt cheap, can be bought for around $50, maybe more if you want it to come with software like DVDXcopy
You should be able to do this for about $750.
Here's one I am looking at:
Chieftec Dragon Mini-Tower Red ATX Case with Front USB, FireWire and Side Fan
Ultra 400Watt ATX Power Supply with 120mm LED Cooling Fan - Titanium-Color
SOYO - KT600 DRAGON PLUS - VIA Socket A ATX Motherboard with Audio, AGP8X/4X/2X/1X, IrDA, USB 2.0, Firewire, Serial ATA and 10/100Mbps Ethernet LAN Support
AMD Athlon™ XP2800+ / 512K Cache / 333MHz FSB / Socket A / Processor / Barton Core
Ultra Copper Base Cooling Fan For AMD Athlon Processors Up To XP3000+
Ultra 512MB PC2700 DDR 333MHz Memory
PNY GeForce4 MX440 Video Card / 64MB / AGP 8X / TV Out
Seagate 120GB / 7200 / 2MB / ATA-100 EIDE Hard Drive
Artec CD Burner / 52x32x52x CD-RW / Beige
Keyboard and mouse
$529!!!!
http://www.tigerdirect.com/applicat...ls.asp?EdpNo=860180&Sku=S450-4102 R&CatId=332