I've learned a lot of lessons. Some I've picked up the hard way by making mistakes and losing money or business. Others lessons, I've been fortunate enough to learn from other writers who were generous enough to share their experiences.
I'm sure there are literally hundreds of books I've turned to over the years, but the following are my current top seven picks. Check them out. You may find that they help you as well.
1. Write. Publish. Repeat.: The No-Luck Guide to Self-Publishing Success by Johnny B. Truant and Sean Platt. Finally, a book about self-publishing for fiction writers! As the authors themselves say, this is not the right book for "pure artists," but if you're ready to work like hell and delve deeply into the business side of writing, you'll find spot-on advice that can help you increase your chances of a long, successful fiction writing career.
2. How to Work for Yourself: 100 Ways to Make the Time, Energy, and Priorities to Start a Business, Book, or Blog by Bryan Cohen. Cohen has written many helpful books for writers, but this one happens to be my current favorite. By turns practical (learn how to take care of your body and set useful goals), philosophical (find things you like and respect about your adversaries), and creative (let yourself daydream, brainstorm new ways to market your product), Cohen offers all the tools you need to help make your writing and authoring dreams come true.