There is a common misperception that we get "all our oil" from the Middle East. If you look at the countries in the Top 20 that are Middle Eastern countries (Persian Gulf area) you will find only Saudi Arabia, Iraq and Kuwait.
Combined, these three countries supplied the US with 617,831,000 million barrels of oil, or 19% of the total from the Top 20.
Of this amount imported from the region, Saudi Arabia represents 64% of the total. Saudi Arabia's imports to the US represent only 12% of the total from the Top 20.
Since total oil imports are approx 50% (a little less in actuality) of our overall domestic oil use, you can cut all those percentages in half to get a rough estimate of how dependent we are on these foreign sources of oil.
Note: the TOTAL amount of crude oil (JUST crude oil) imported to the US from ALL sources in 2010 was 3,362,856. The Top 20 countries above provided 97% the total amount imported. While my calculations are not exact, you can see they will be in pretty close proximity.