Just enter your zip code in the site below and it tells you which gas stations have the cheapest prices (and the highest) your zip code area. It's updated every evening! They are listed from the lowest (at the top) to the highest (at the bottom). At the very bottom of the page it will tell you where the lowest and highest gas in the country is as well as the national average. Cool! 
http://autos.msn.com/everyday/gasstations.aspx?zip=&src=Netx
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http://autos.msn.com/everyday/gasstations.aspx?zip=&src=Netx
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