Haha I can give you a 1000 dollar build but Tower only ! No mouse, keyboard, monitor, etc.
Coolermaster HAF 932 Advanced Full Tower $120.00
ASUS M5A97 Motherboard $94.99
AMD Phenom II x4 965 $89.99
8GB Kingston KHX1600C9D3B1K2 2x4GB DDR3 $42.99
Coolermaster Hyper 212 Plus after market CPU heatsink $29.61
Western Digital 1TB HDD $89.99
ASUS DRW-24B1ST DVD/CD Drive $24.98
ASUS GTX 660 Ti OC edition $289.99
Coolermaster Silent pro M2 720W PSU $96.52
That's everything you need and all the prices are from NCIX.
Total would be: $983.43 CAD Including 12% HST
This build can definitely run games like Guild Wars 2 or Battlefield 3 on highest graphics setting and at a constant 60 FPS. Also the full tower can ensure your future upgrades to fit in (if u are planning to upgrade it in the future).
Good luck!