You may not be aware of this but most times when you end up with spoofed emails from your domain (not to mention lots of unwanted spam) it is because the email addresses were origionally "harvested" off of your web pages with a robot or spider built specifically to collect them.

You can protect the email addresses on your web pages by using the following Javascript code where you would like your email address to appear. I have aptly named it "Spam Bot Killer"

<script language="JavaScript">
<!--
// hide script
var stb_domain = "yourdomain.com"
var stb_user = "theaccountnamehere"
var stb_recipient = stb_user + "@" + stb_domain
var stb_url = "mailto:" + stb_recipient
document.write(stb_recipient.link(stb_url));
// -->
</script>

Change the "yourdomain", of course, to your domain name and the "youraccountnamehere" part to whatever is before the @. The link will show on your page as youraccountnamehere@yourdomain.com and it will be clickable. However the bots and spiders will not be able to harvest your email addresses any longer.

Hope this helps! Enjoy.