I received something in the mail that takes place of federal forms 1099-G and 1099-INT that shows the total overpayment from 2015. Where/how do I enter this?

The form 1099-G/INT is basically two forms in one.  The information shows the amount of refund, credit or interest issued to you in a calendar year.  If the form only shows over payment, that is your refund. If it also shows interest, you may have multiple data entries.

Please enter amount of the refund (over payment) showing as if you received form 1099-G. 

1. Federal Taxes
2. Wages and Income
3. 1099-MISC and Other Common Income, select State and Local Tax Refunds on form 1099-G

IF you also have interest, please enter it as if you received 1099-INT:

1. Federal Taxes
2. Wages and Income
3. Interest and Dividends, select Interest on 1099-INT