Hamster got out of cage for 2 days?

It's been two days since he disappeared! I don't know what to do. My hamsters live in the garage, and when i checked on him, he was gone. the top fell off when a snowboard hit it. usually my garage stays closed but yesterday my brother left it open for about 5 hours. I don't know where he is! I have a weird feeling he's outside but it's been 2 days and i don't know what to do. PLEASE HELP!