How can I switch from mailing in the forms for state of iowa to E-file?

Yes, you can switch to e-file for your state return as long as you haven't printed, signed, and mailed in the return yet. 

Here's how to do that:

1. Sign in to your TurboTax account.
2. Select Add State.
3. Select Review from the left-side menu  (expand your browser window if you don't see this, or select the menu icon in the top left corner).
4. Address any details that come up.
5. Select File.
6. On the Just one more step screen, follow steps 1 and 2 if you haven't already.
7. Select  Start to the right of step 3.
8. On the Let's get ready to e-file screen, select I want to e-file to the right of your state..
9. Follow the on-screen instructions to e-file your return.