Mid-city Auto ripoff Milwaukee Wisconsin

My son is away at school and lost his job in december. The motor on his engine went out and he took the last of his savings and paid mid city for an engine. They promptly took the money out of his account in January. However he has not received the engine therefore leaving him without transportation and money. He has called this company on numerous occassions inquiring about the engine and was told that the engine was sent out. When he asks for a tracking number he is told to call back the following day. Unfortunately when he calls back the next day they do not have the tracking information available. i found this site because i was looking for the 'Fair Business Association of America' which is the organization that is listed on the website. Unfortunately i found that there is no such organization. What should my next step be so that i can assure that my son does not get ripped off.

Leslie
brooklyn, New York
U.S.A.