I thought this might be a useful item to post. I printed out a copy to keep in my truck. Del http://www.pilotflyingj.com/assets/templates/pilot/images/RVTG%202012.pdf
What I have been doing is checking gasbuddy.com; on a cell phone, they can show you the best prices around your location. Hardest part is finding the station, and then determining if that price was cash or credit.