You can also search for "unlock code" on ebay. It could cost anything from $5 to $50, depending on your device brand/model.
It's better to get the original carrier to provide the unlock for free, if that's an option.
There's no universal unlock codes or unlock keygens online anymore - you have to get the unlock from someone who has access to the registries (which costs money) or you have to install hacked/modded firmware (which isn't available for every device and which may not defeat the carrier-lockout anyhow).
