Can you buy an iPhone without buying a contract?

I currently have an iPhone 3G, and I want to upgrade to the 4S. However, my cell company (TMobile) does not have a deal with Apple. I would like to buy an iPhone for the advertised price (not the unlocked price of $500+) and unlock it myself. Is there any way I can buy an iPhone from Apple without buying a plan with AT&T, Verizon, or Sprint?

A contract-less phone and an unlocked phone are going to be the same price. The reason it's so cheap is because they basically loan you the phone and you pay it off over the course of your contract.

The only other option is buying the 4S on Ebay.

They usually average around 300-370$.