Where can i enter tax withheld (i.e. paid) in my Wisconsin state return?

UPDATED FOR TAX YEAR 2019

If you mean tax withheld from your paycheck, just enter your W-2 in the federal return and the WI taxes withheld will flow to your WI return. 

If you mean payments quarterly payments of estimated taxes, please follow these steps:

1. Click on Federal >  Deductions & Credits
2. In the Estimates and Other Taxes Paid section, click on the Start/Update box next to Estimated Tax Payments. 
3. On the next screen, click the Start/Revisit box next to State Estimated taxes for 20XX.
   
4. Enter your payment(s) on the next screen, How much did you pay in state  estimated taxes? Select the state from the drop-down list and enter the amount paid in the box.

[Edited | 4/10/2020 |  9:06am PDT]