installing 93 accord bose amp.

the aftermarket radio of my car was stolen, and when i when to get a new radio installed they said my amp must have been stolen too, because thats all i needed to get my new radio to work. So i bought a new bose amp. and plugged it in but it still does not work. i was wondering if i neeed an extra part or somthing. i dont want to take it back to the stereo shop bc they are exspensive