@dkhoweatt also asked: "how do I enter the amount of tax Okla. withheld from my income?"
The Form 1099-MISC that you will get from the oil/gas company should show you the amount of state income and state tax withheld in Boxes 15-17. You enter all the info from your 1099-MISC into TurboTax in the Federal interview, and the state tax withheld "should" flow to the state tax interview when you start the state return. You may be able to doublecheck it when you go through the state interview to see that it did. In any case, be sure to print and review the Oklahoma return prior to filing to make sure you are getting credit for any withholding.
