> where do I plug my battery?? <

The battery pack could be plugged into any unused channel. If you need all 4 channels then get a Y-connector so that one channel will go to a servo as well as to the battery pack.

You can buy a Hitec Supreme receiver for $63 from Hobby Lobby or a Futaba R127DF receiver from Tower for $73, both including crystals. Not a lot to pay for good gear.