Here's a 1.6 Dual core with 512 for $900, video card is kind of anemic. You'd want to add at least another 512 of RAM so all in you'll hit $1K. It's Lenovo, formerly IBM. It's a name brand and IBM's were rock solid durable boxes. Have not heard of any drop in quality since Lenovo took over.
http://www.pcconnection.com/ProductDetail?Sku=6897154&oext=671B
I think a more realistic price is going to be at least $1k and $1.3 should get you there.
If you are a student look for educational discounts, might get you 10% off.
Here's a list from cnet,
http://reviews.cnet.com/4566-3121_7-0.html?filter=100021_13182944_
Good Luck.