What do I do if I am buying a car from a dealership but what they said in the ad was not completely true?

Question Details: I went online looking for a car and found an 07 Cadillac CTS for $4500. We thought it was a good deal, so we called the car lot talk to a manager. A deal was made and I gave them $1500 down about 2 1/2 years ago. The car was not ready to be sold as the previous owners are having issues with their bank. So how can they seal it to me like that? I did everything they asked me to do; I even have insurance on it but I still don't have a car. What do I do?
