The wireless device for doing this is called iTrip. It plugs into the bottom of the ipod/iphone and you just select a frequency of "blank" air (which will be plentiful!) and match the frequency of the iTrip to the one on the stereo, press play on the ipod and off you go. You do have to keep them relatively close together to get a decent uninterrupted signal but on the passenger seat or somewhere on the dashboard works fine.