HELP - i need a script to redirect and manage hits from my banners...

[cmedia]

Hello.

i have some traffic and i redirect this traffic to my sites, using generic banner.

so, user click on banner, without know what site will see.

the problem, is like this i receive too hits from same user, on the same site.

i mean, the same user click 3 times on different generic banner, but both 3 times be load the "SITE A".

i want the user each time is redirect to a different site.

first click to SITE A second to SITEB third to SITEC etc...

i tried to search a script who count the hits and do this, but i don't founded.

exist something like this?

thank you.