why dont you track them yourselves?
that way you could even see from what thread a user click to get to your site.
it will take you all of about 15 lines of PHP code to do this, and insert into a database.
for instance you could add something like
www.yourdomain.com/?click=dnforum to your signature
then
something like
<?
if (issset($_GET("click")) {
$camefrom = $_GET("click");
$referer = $_SERVER["HTTP_REFERER"];
}
Then do a simple database insert
Insert (id, camefrom, referer) into TABLE Values ('','$camefrom','$referer')
or something like that..
for DNF to do it would be very simple, but better if you done it yourselves.