i just turned off my google adwords campaign.. its just flat ridiculous.. heres the scoop to help save you people some money. I put my product and price right on the google ad.. to deter as many people as possible who werent looking to spend money. $10 monthly web hosting on googles awesome content network here are my stats. 6723 visitors over all time. and one sale that was fraudulent.. meanwhile I get other traffic with a 30-1 convert rate.. and other traffic with a 100-1 but 6700-0 is just flat very very very poor traffic.. dont let the big google name fool you .. If you want good traffic you need to use adwords for google search engine only.. and then you wont be able to afford the traffic at 5 bucks a click ..
I had the same problem with Adwords for web hosting programs. I turned my campaign off when I reached 400 clicks with zero sales.
It's may be fraudulent click too now. Last week i was looking for Google adsens books on e-donkey and i also found softwares to generate adsens click. Not really good for the futur
There are some areas of the content network that you might want to avoid if you want to avoid click fraud. Topics would probably include web hosting, mortgages, credit cards, and of course methoselioma. Anything you receive spams about are also areas I think fraudsters would be active in. I find the content side to be as good or better than search but certain niches attract fraud.
In a hyper competitive space such as web hosting, a long tail approach to keywords might have performed much more effectively. Brian