I have looked all over and am unsuccessful on the list of characters. It seems in all I have read that his characters for this book may not be as dynamic and developed as in his past books. However, there are a plethora of book reviews out on this one...some are positive, some not so much. The links are below for the book reviews, and I have included an enotes link for Grisham biography information, although the book (The Appeal) in question is not mentioned since it is a relatively newly published work.
Good Luck in your endeavors!