I need to track email newsletters, how?

It is done by having a database where you ign an ID to each email address. When you send the email, you add a query string to every URL in the email. For example, joe@aol.com might have the ID of 12345 in your database. So, instead of having a link like a href="http://mysite.com," rel="nofollow"http://mysite.com,/a you have a href="http://mysite.com?acct=12345." rel="nofollow"http://mysite.com?acct=12345./a Now, when the person goes to your site, you have a script on the server that checks to see if acct is in the query string. If it is, you know account 12345, which is joe@aol.com, clicked on the link in his email - or forwarded the email to a friend who clicked on it - or someone saw the email and clicked on it without telling Joe about it.