Diesel Gas @ Unleaded Pump

I was in a small east Texas town and few months ago and purchased gas at a convenience store/gas station. My car (2001 Toyota Camry) spit and sputtered all the way back home. The next day it would not crank at all! Upon having it towed to a dealership, I was told the tank would have to be dropped and drained because there was diesel fuel in the tank. I am certain I did not purchase gas from the diesel pump, because it is located away from the unleaded pumps. Well, I ended up spending $1100.00 to repair my car. Is there anyone out there that has had this problem. What recourse do I have? Is there a state or federal agency where I can file a complaint? (I live in Texas) I went back to the station, and was told that that could have never happened with their gas, because it is tested biweekly. Well, it happened, because it was the only place I got gas and it didn?t happen until I filled up there---Somebody plz help!