Each email you receive comes with headers. The headers contain information about the routing of the email and the originating IP of the email. Not all emails you receive can be traced back to the originating point and depending on how you send emails determines whether or not they can trace the email back to you. The headers don't contain any personal information. At most, you can get the originating IP and the computer name that sent the email. The originating IP can be looked up to determine from where the email was sent.