Google PPC and Seller Review Ratings

Notice the star ratings against your competition’s PPC Ads? If you worry they attract customers then you should. They do.
So where do they come from? Google aggregates them from a number of sources: Reseller Ratings, Bizrate, and Viewpoints.
Each service works differently.  But looking at BizRate, to use their service you need to sign up with BizRate Insights. You then would then have to add some code to your checkout success page to invite customers to give feedback.
So how does Google match those reviews to your Ad?  They do it based on domain name.
To read more about it read some Google Q&As.