For $1k you can easily get a beast of a setup, similar to my setup i'll be purchasing in a few weeks:
-Silverstone Raven RV01 Case = $250
-Gigabyte GA-MA770T-UD3P motherboard = $135
-AMD Phenom II 965 Quad Core 3.2Ghz = $300
-4GB 1600Mhz DDR3 Ram = ~$100
-750W Corsair PSU = ~$200
-Decent GFX Card = ~$200-300
give or take a few things, swap them around, like getting a cheaper case for instance and putting the spare cash into the gfx card or whatever.
Basically, build your own setup and build a beast.
If you live in Brisbane, go for either uMart, or Gamedude.com.au, personally I prefer gamedude as they're usually the cheapest around.