At Amazon.com you can find a list of the top 25 purchased books. Currently, 17 of the 25 have been mentioned on the Glenn Beck Program or he has had the author on the show.
I only mention this because there are those who are conservative but discredit Glenn by saying that he is fantastical and conspiracy prone for the ratings. This is clearly untrue and they should start listening to the show. There is a rapid turn towards the Founders and the founding of this country and this is where it is beginning.