1099-R, I took a distribution, paid the federal & state taxes, but do not see a section in turbotax where to put the taxes paid on the distribution.

Yes, I see they were reported on boxes 4 & 12, but don't they get entered somewhere on TurboTax like a W-2?

As mac_user22 states below, you'll enter this information in the 1099-R interview. You can scroll down on the 1099-R screen to see boxes 4 (federal income tax withheld) and box 12 (state income tax withheld.)

Enter a 1099-R here:

Federal Taxes,
Wages & Income
I’ll choose what I work on (if that screen comes up),
Retirement Plans & Social Security,
IRA, 401(k), Pension Plan Withdrawals (1099-R).

OR  Use the "Tools" menu (if online version under My Account) and then "Search Topics" for "1099-R" which will take you to the same place.

Be sure to choose which spouse the 1099-R is for if this is a joint tax return.
Be sure to pick the correct 1099-R type: Standard 1099-R, CSA-1099-R, CSF-1099-R, RRB-1099-R.

[NOTE: When you get to the "Your 1099-R Entries" screen where you can add another 1099-R, use "continue" to keep going as there are additional interview questions after that screen in most cases. You can always return as shown above.]

The box 4 tax will get added to all other tax withholding and go on line 64 on the 1040 form to offset your overall tax liability.

If the taxes were withheld from your distribution, they should be reported on the 1099-R (federal taxes in box 4 and state taxes in box 12.) You may need to scroll down on the 1099-R screen to see the box 4 and box 12 fields. (Click the first two screenshots below for reference.)

Note: If you paid the taxes directly to the IRS and/or the state (i.e., they weren't withheld from your distribution), they won't be reported on the 1099-R. In this case, you can enter them as estimated tax payments:

• Open (continue) your return in TurboTax Online. (If your return isn't open, you'll need to sign in and click Take me to my return.)
• Click My Account (top right of your screen).
• Select Tools.
• In the pop-up window, select Topic Search.
• In the search bar, type estimated.
• In the results box, highlight estimated tax paid, then click GO.
• You'll land on the Estimates and Other Income Taxes screen. Click Start next to Federal estimated taxes for 2016 (Form 1040ES). (Click the third screenshot below for reference.) (You can also select state or local estimated taxes, or scroll down to select taxes paid with an extension, 2015 refund applied to 2016, or other income taxes paid in 2016.)
• Follow the onscreen instructions to enter your federal estimated payments. (Click the fourth screenshot below for an example.)
• After you enter your federal estimated tax payments, you'll return to the Estimates and Other Income Taxes screen, where you may enter additional estimated tax payments, as needed, for example State estimated taxes for 2016. 

Note: If using the TurboTax CD/Download software, you'll use the Find function (instead of "My Account") to search for the topic.

[Edited 04/13/2017]

You do not enter 1099-R tax in estimated tax - it is entered in the 1099-R section.