In a side project I had to integrate a ad manager into a existing website. In fact all that there is to be done in add JavaScript or any other suitable tags to the HTML page. The big part is the ad manager. In the quest to find the good one I stumble on OpenX ad manager. This is by far one of the best open source well thought software.
From a no nothing start point I think that the software is simple and straight forward enough to get you set up in a day. Download it, navigate the forum to get the little extra information to how to price and where to place ads. And you’re ready to go.
This software just gets me going, big thanks to the team for making this great open source software.
OpenX give you a bunch of features, see http://www.openx.org/en/products/benefits.
http://www.openx.org/
http://forum.openx.org/