Dave is a perrenial salesman. I don't mean that to sound bad. I have heard that there is a lot of information in his books. There are a lot of other sources for similar information. I will give Dave this credit. He is honest, and his information, if you use it< is effective.
You can also research a lot of information on the various websites. You will find a link section that has most of the current BBS's on it.
Scot Stone