Some honest advice for you: the market for retro gaming is difficult in Calgary. You've got the shops selling games at a markup, and you've got people who regularly scour the pawn shops for anything worth buying. Even the pawn shops know to markup the rarer games a significant amount. If you're looking for some crappy games just to fill your collection count, then you can look at these places though.
I would suggest first contacting CP member Kelekin for any specific games you might be interested in, as he manages a large collection of games to sell at conventions and on his website (
http://www.newgameplus.ca/). Otherwise I'd start keeping an eye on the regular sellers on ebay for this kind of stuff.