You have a novel or instruction book in your head. Everybody does. Maybe you have even started writing. Should you find an agent, finally get a publisher, etc.?
No matter where you are in the process, get Christine Rose’s book Publishing and Marketing Realities. She gives one a real honest look at the book business–based on her experience. You don’t want to make the same mistakes she has made. I made different mistakes and am still contemplating more mistakes. It is a wild and changing business. The best advice she give is, that if you wish to get wealthy by writing a book, your chances are better if you just buy a lottery ticket every day. It’s a much easier and a smaller investment.