Darien is correct.
If the email is from a larger host that won't be too site-specific, you can check the message header for IP address it was received from. Then you can do a trace and if it is a local ISP you can get pretty close to where they are from, and for sure you can get the contacts for the ISP.

I like to paste the address or domain into NeoTrace, a really handy little shareware program from download.com

it is fully functioning, just it is a shareware license, so technically if you want to keep it forever it would be nice to send people cash but I haven't gotten around to it yet.