Where on my 2016 tax forms do I find the answer to "total of all of your payments and withholding" for figuring out if my 2016 state tax return is taxable in 2017?

If you have a copy of last years return, see if you took the standard deduction or if you itemized deductions. If you used a 1040A or 1040EZ, you used the standard deduction. If you used a 1040, it would show which you used on line 40.

If you used the standard deduction, the refund is not taxable. 

If you did itemize deductions, but you used the state sales taxes paid (schedule A line 5b), rather than the state income tax paid (schedule A line 5a), the refund is not taxable. 

If the refund is taxable, report it. If it is not, you do not need to report it. 

All tax payments and withholding from last year is found on last year's schedule A line 9.