(adsbygoogle = window.adsbygoogle || []).push({}); Is there any way to get the email someone used to create there steam account?

Unless you Keylog them and catch them typing in their email and password, there is no other way. The information for that is stored on Steams servers. When the user types in their Email and Password, a verification is done and if it matches access is granted. If the person stores the log in information on their computer and you have a RAT available, you could use that in order to try and fetch his information.