You received a Form 1099 (with NO prefix or suffix), generally limited to interest paid *by* the IRS on delayed tax refunds; that interest is taxable by both the IRS and your state. (Though paid by the Federal government, it is NOT exempt from state taxation because it's not from a Treasury security, U.S. Savings Bond, or other government security.) Since it's essentially the same as a 1099-INT issued by private payers, enter it in TurboTax as a 1099-INT in the interest section.
