Tracing E-Mail Addresses

Have you ever received an email from someone and really wanted to know sent it. I'm not talking about finding out who sends you spam or junk mail. I'm talking about a harrassing, threatening, or suspicious email; or maybe even an email you found on your spouses computer (you know, the one he or she didn't want you to read).

Check out this blog on the topic, it is extremely thorough.