Well, according to the Energy Information Administration(http://www.eia.doe.gov):

Can I tell which country or State the gasoline at my local station comes from?

For several reasons, the Energy Information Administration (EIA) cannot definitively say where gasoline at a given station originated:

1. EIA does not collect data on the source of the gasoline sold at retail outlets.

2. The name on the service station sign does not tell the whole story. The fact that you purchase gasoline from a given company does not necessarily mean that the gasoline was actually produced by that particular company's refineries. While gasoline is sold at about 169,000 retail outlets across the nation1, about one-third of these stations are “unbranded” dealers that may sell gasoline of any brand2. The remainder of the outlets are “branded” stations, but may not necessarily be selling gasoline produced at that company's refineries. This is because gasoline from different refineries is often combined for shipment by pipeline, and companies owning service stations in the same area may be purchasing gasoline at the same bulk terminal. In that case, the only difference between the gasoline at station X versus the gasoline at station Y may be the small amount of additives that those companies add to the gasoline before it gets to the pump.

3. Even if we knew at which company's refinery the gasoline was produced, the source of the crude oil used at that refinery may vary on a day-to-day basis. Most refiners use a mix of crude oils from various domestic and foreign sources. The mix of crude oils can change based on the relative cost and availability of crude oil from different sources.

So, maybe I could've let you go out there and buy gasoline from only certain gas stations in hopes to either stop the import from certain countries or lower the gas prices, but I believe that ignorance isn't bliss. The misunderstanding is that oil companies extract or import, refine and then sell that specific oil, or that if you only bought from certain gas stations that they wouldn't have to eventually buy their fuel from other oil companies anyways. The only suggestion I've heard that could actually work is to strengthen the U.S. dollar, and that my friends has no easy solution either. If things get worse before they get better we'll just have to realize that driving has become a luxury and we'll spend our money on the increasingly expensive necessities because those items all had to be driven into town on trucks.