Just in case newbies see this thread and don't understand what "testnet" means, testnet is a way to test Bitcoin functionality without working with the official public blockchain. This means that any and all transactions through testnet are only usable within the testnet for testing purposes. While, in theory you could pay for things using the testnet, it's like accepting wooden nickles for your services. Sure, you get something, but it's just junk.
You can learn more about the Bitcoin testnet on the
Bitcoin.it Wiki.