The book is called Corvette Thunder, and is available from Dick Guldstrands web site. Friedman and Guldstrand signed a lot of them, but I also know that they don't update the website a lot.
http://www.corvettethunder.com/
There is also another one about the L88 racing Corvettes with lots of great race photos.
http://www.corvetteracinglegends.com/
Both are worth checking out.
Steve