Most people already know the basics – stay away from gas stations in rich neighborhoods and near expressways or superhighways – their costs due to real estate location are higher and they have somewhat a captive customer base, so they almost always charge more.
Very few vehicles actually get any benefit from “premium” gasoline. Check your owner’s manual, it isn’t “cleaner,” “better for your engine,” or “more powerful” unless your engine is designed to use the higher octane – usually this means a muscle car.
Also, with modern computers and knock sensors in cars even those whose power can benefit from premium gasoline may be able to use regular grade with no problem.
Shopping for the best price is also important.
One web site getting lots of traffic these days tracks local station prices in most parts of Canada and the U.S.
Check your area by ZIPcode, county, or city.
In small towns there usually isn’t much difference and certainly not enough to justify the fuel used in driving to a distant station.
For example, in a nearby college town, Indiana, PA, all the stations where charging $3.49/gal of regular.
But in relatively large towns and certainly near a city this can be a powerful money-saving tool.