For $50 you can unlock your iPhone with Telus.

Here's how, according to Telus:

1. Call Client Care to request the phone unlock. Numbers to call in Canada
2. The Client Care representative will complete the steps to unlock your phone.
3. Connect your iPhone to iTunes and wait for the message "Unlock Complete. Congratulations, your iPhone has been unlocked. To set up and sync this iPhone, click Continue".
   NOTE: NOTE: An Internet connection is required in order for iTunes to unlock your device.

I'd add that it's important to note that there's two NOTE:'s on Telus' page¹ so that must mean it's very important.

Apple offers a few additional suggestions before unlocking your phone - the most important of which is to back it up before you do anything.

Unlocking your iPhone allows you to take it to a different phone carrier - any carrier. Typically when you buy a phone you sign a 3 year contract and the phone you get is locked to, as in will only work with, the phone service you're buying the phone from.

Via iphoneincanada.ca - where they make use of the awful advertising plugin that makes certain words appear as links and when you accidentally hover over them you get a pop-up ad. Disgusting.

1. Screenshot link in case they fix it by the time you're reading this. ↩