Gas Buddy

I posted earlier this month on a great local website to check for gas prices in the Michigan area. I'm sure by now most people know you can check for gas prices in every state. The main source for the site I use is located at GasBuddy.com and covers all of Northern America.
It's pretty cool because you can see which state has lower or higher gas prices then your own, including Canadian fuel prices. As far as in the US they have a page called 'USA National Gas Temperature Map.' By viewing a color coded map with red being the highest areas in prices and green being the lowest you get a general idea of where the lowest priced spots are in the United States.

Gas Buddy pretty much depends on consumers logging in and entering data on local fuel prices. I've found a few favorite stations that are usually the lowest prices in my area. Some stations will compete but rarely are they lower and it's usually because they're in a more convenient location to fuel up so prices are usually few cents higher. I've never had a day out though when I haven't fueled my tank only to later find a station not in my area with lower prices. Oh well, whats the old saying... don't cry over spent gas.