You could code (or get coded) a system in PHP with ad start times and dates, manually deletion and of course tracking. Where you could keep track like this:
Say for instance NamePros was one of your advertisers.
You could have like:
http://yoursite.com/out.php?id=11 for everytime someone visits NamePros via your website.
http://yoursite.com/in.php?id=11 for everytime someone visits Your Website Via NamePros.
These systems are easily coded, and if you are a php coder you could do it, if not there are many people able to do it.
Hope ive helped.
