On State Form where do I show Estimated Tax? Never was asked about it and unable to find where it should be entered.

You enter estimated tax payments made to both federal AND state within the federal interview.  You'll enter these payments under the "Deductions and Credits" section of your TurboTax interview.  See the instructions in the TurboTax FAQ I'm linking below.  

Where do I enter my estimated tax payments? 

Here's a screenshot