Here in Canada we've got Future Shop, the Source (by Circuit City), ummm Wal-Mart (:lol:)... Then a bunch of random small businesses. At least that's whats up there in the Soo. But down low in the Toronto and Niagara area and whatnot where DZ is, there's prolly a crabload more.
The Specs for the computer mentioned in the first post:
http://www.bestbuy.ca/catalog/proddetai ... &langid=EN
The nVidia GeForce 7050 doesn't seem too great from the reviews I've read about it, but it's not bad. It'd be best if you researched this yourself so you could decide what you want your card to be able to do.
2GB of RAM is enough to run Source and Garry's Mod, probably enough to do video-editing too. The processor, Intel Dual Core E2180, should also be researched. Lastly, it comes with Windows Vista Home Basic. From what I've read, Basic is the crab version of Vista. If you are to get an operating system, get Linux, XP or Vista Home Premium. However, you've said before that you don't really like Linux, and XP is losing (or has lost) Windows' support. I would go for Home Premium.
Therefore, I would suggest looking elsewhere for a computer. You could see if that crazy-awesome Acer that Lase posted is sold in Canada. If so, get it. It's pretty much an amazing computer for an amazing price.