Are you using TurboTax CD/Download or TurboTax Online?

CD/Download.

In EasyStep Mode, select Review > Audit Defence from the left side menu.

Purchased for $135.00 CD download version from Staples. I just finished submitted Netfiled. The turbo tax only want my review of the software.  The program did not give me an option to purchase audit defence for our tax returns. I was told that I would be able to purchase by a tax expert when I was net filing.  Where can I purchase audit defence?   Link please 

Unfortunately, you can't purchase audit defense after you have filed.