http://store.apple.com/ca/browse/home/shop_iphone/family/iph...
Then you can stick whatever SIM card you want and it'll work. Unfortunately, you'll be stuck with paying a lot at the beginning for the phone. It's also possible that you can get your carrier to unlock it; I know some UK carriers will.
Not sure how a SIM-locked iPhone is any different to any other phone that's SIM-locked - any pretty much any phone that's subsidised will be locked.
http://store.apple.com/ca/browse/home/shop_iphone/family/iph...
Then you can stick whatever SIM card you want and it'll work. Unfortunately, you'll be stuck with paying a lot at the beginning for the phone. It's also possible that you can get your carrier to unlock it; I know some UK carriers will.