First you will need to determine the provider in order to send it to their internal abuse inbox. If the spam came from someone@hotmail.com you would forward the email to abuse@hotmail.com. If you're using a web mail service (such as hotmail, yahoo, ail) you there should be a report as spam button come up on your top bar when you click on the email. Lastly, and perhaps most importantly, you should report it to the FTC. You can find more information here: http://www.ftc.gov/spam/
