This article will describe how you can pass in a user's email by referencing it as a property.
If your system is set up with LDAP/AD to pass over the email information for your users or a local user with the email address field filled in, then you should be able to reference the user's email as follows $[/users/
C:\Users\ecloud>ectool getUser test
C:\Users\ecloud>ectool getProperty /users/test/email
You can dynamically reference the property so that the user who runs the job is the user whose email is passed in by using $[/users/$[/myJob/launchedByUser]/email].