Advertising: Selecting a pay-per-click affiliate
Acceptance to a program usually takes about 24 hours. When you join, they will send you the HTML text for their ads. This HTML text is pasted into the "Advertisements" screen in the Fluid Dynamics Search Engine.
You can have as many Pay-Per-Click companies as you want. They all tend to be free to join. The FDSE advertising module allows you to mix and match ads from many different Pay-Per-Click companies. You can also mix in your own advertisers.
"Advertising: Selecting a pay-per-click affiliate" http://www.xav.com/scripts/search/help/1040.html