How do I add another account to my email?

[Critter-3]

You can have up to 5 different user accounts linked to the same email address.  Just don't use the email address as the userID.

[DoninGA]

You can have up to 5 TurboTax online accounts associated with only one email address.

You have to create a new account.  

Go to this TurboTax website and click on Sign Up to create a new account - https://turbotax.intuit.com/