Hi,
Have you ever used Google Adwords for Affiliate marketing?
Yes indeed I have and successfully! But it took some time to get there....
You need to be aware of G's strict policies such as information harvesting which stops you from collecting emails and building a list, user safety which means no exaggerated claims, disclaimers, disclosures etc as well as the bridge policy which prevents most affiliates from using adwords in the first place! There are also many other polices which will make your eyes bleed and your head hurt lol... My best advice is to spend a considerable amount of time learning adwords as chances are you'll lose your account before you even have your first campaign launched...
The back end system to adwords can be somewhat complicated and taking the time to learn this will save you money - and finally with adwords you really need to keep an eye on conversions per keyword (SEM PPC), otherwise you''ll make a loss in some cases ... a massive loss!
Being blunt - unless you know what you are doing - I wouldn't even try as an affiliate to advertise on Adwords... Like I said the bridge policy makes it almost impossible.... As a vendor you'll have a much higher chance of success as if you get into trouble with the manual review you'll be able to make changes to your site, but as an affiliate you wont get that opportunity and chances are you'll be banned for life.....