I will be offering three types of advertising on my site: banner, a text listing and PPC (such as Yahoo and Google). I need help in locating a software that I can use to keep track of PPC's. Any suggestions would be greatly appreciated.
You will have to custom build your own software.
But if you simply want an ad server where you could serve various types of advertising and track the number of clicks made, check out Openads http://www.openads.com — it is an open source program that is FREE yet very well done with great features.