You get most of your oil from Canada.
From the Energy Information Administration:
"The top sources of US crude oil imports for May were Canada (1.877 million barrels per day), Mexico (1.576 million barrels per day), Saudi Arabia (1.457 million barrels per day), Venezuela (1.169 million barrels per day), and Nigeria (1.075 million barrels per day). The rest of the top ten sources, in order, were Iraq (0.666 million barrels per day), Angola (0.356 million barrels per day), Algeria (0.350 million barrels per day), Russia (0.255 million barrels per day), and Ecuador (0.239 million barrels per day)."
US domestic production is 4.21 million barrels per day.