Returned Auto Parts: Did not get money or parts back

I phoned in an order to Ultraperformance Parts in Tucson AZ for a part for my car. After 1 1/2 weeks, no part. I called them back up and they told me that they did not have the part in the color that I wanted and that they would have to order it directly from the manufacturer. I asked them if they could second day air ship it and they said they could, but to call them back to confirm shipment type (5 day ground or 2 day air). Business took me away from the phone and the city for a few days. While on business I found the exact part I wanted and bought it. After I returned home a week later, I had a box on my doorstep. It was the part from Ultraperformance (which I thought was odd since we never finalized anything). I immediately called them on the phone to arrange a return. They weren't very happy at taking the part back, but eventually agreed to it and gave me a return authorization number. I sent the part back to them and now, 3 weeks later, no repayment and no part. I called them today to get an explanantion but the person I tallked to said "John took that order and he is not here today, and I can't read his notes other than he refunded your shipping charges to you on the 11th of Feb, so call him back tomorrow". Now this is a total lie because I have on line banking and I show no refunds whatsoever from them on the 11th or any other day. So in essence, they have added insult to injury by not only keeping my money but also my part and they have not tried to contact me in any way to let me know they were screwing me (I'm sure in the hopes that I would never notice that they did not refund my money). I called them Sat. 20 Feb and talked with John, he said that he was not going to refund my money because the parts I sent back were not the exact parts sent by the factory (true: the part was not the EXACT part, but it was the same part just different in color). He said that by accepting it this way it would screw up his inventory, despite the fact that it was the same part number. He then offered to send me the part back at my own expense. It was then that I decided get my bank involved by filing a credit card fraud complaint against the company. Hopefully this rip off report system can HELP ME GET MY MONEY BACK as well.