Contact your ISP about where to send or visit their homepage and look for it. Also send a copy attached to the FTC:
[email protected]
Here are the instructions on how to do it:
http://www.consumer.ftc.gov/articles/0038-spam
And file a complaint with the FBI through IC3, the cyber crimes division f the FBI. You can attach a copy of the email to the complaint:
http://www.ic3.gov/default.aspx