I have always thought this was a nice site in general. http://www.carbuyingtips.com/
It doesn't seem over bloated with ads or pop ups.

But they have a very nice section on top 10 dealer scams and add-ons.
http://www.carbuyingtips.com/scams.htm

I really like that they explain the scam and how it works.
I see many tip sites that will say 'Avoid the full moon scam',
but then never explain what they mean or just touch on it.


Hope it helps,
Jim