Extreme Auto Sales Jet Speed Motors I have a handwritten IOU that got me to but the car, now they won't honor it port richey, Florida

I bought a car from Extreme Auto Sales in November 2011. I would only but it if the ac was fixed and the headliner was put in. Well, the guy wrote me out an IOU, and I bought the car. The ac was fixed only because I had to hound them constantly. Well, I have been waiting for them to fix the headliner and I keep calling. Now they say the company  is Jet Speed Motors and I am screwed.

Well, a few minutes after getting off of the phone with them, a guy from the shop called me back, he said I know that car, I remember that, there is no need for a lawyer or anything, I will call you next week to set up a time to come in and get this done. Well, that was a month ago. So I called this morning, now the guy I talked to they say is no longer associated with them and once again I am screwed. Really?