I have worked with some authors for almost five years now, and in a few cases they sell more books now than they did when their book was first released. In fact, their sales increase with each passing year. How is this possible?
1. They target their niche market, not just bookstores. There is absolutely nothing wrong with selling your book in a bookstore. If stores have picked up your book and they are stocking it on the shelf, that is great. But shelf space alone won't sell your book. Who is going to buy it? Your target audience. If you have a web site or blog (you should), then be sure to tell your readers where your book is available. Whether you realize it or not, you wrote your book for a specific audience. Sell your book directly to them. If you have written a romance novel, target blogs dedicated to romance novels, visit book clubs, do events at gift shops, and locate events frequented by lots of women (the target audience of romance novels). Do this enough times, and you'll start generating the best advertising of all for your book: word-of-mouth.
2. They write more than one book. Can your first book be made into a series? Readers who loved the first book will buy the second, third and following books in the series. If a reader discovers the second book first, they will want to go back and read the first book to get the back story. If you have built a good fan base for the first book of a planned series, then you'll have a ready-made audience for the subsequent books.
3. They don't stop marketing their book. Some authors give their book marketing the good ol' college try for a few months, get discouraged or lose interest and then just stop promoting their book. Big mistake. Developing a following as a writer is a lot like starting a new business. Success isn't going to come overnight, and it takes time to build a list of loyal customers (readers). The first few months after a book's release is a good beginning, but the best could still be ahead of you. One author I work with has been interviewed for a documentary on the History Channel, but that opportunity didn't come along until her book had been out for more than three years. What if she had given up after the first year?
4. They target new readers. OK, so the book has been out a couple of years and has sold a couple of thousand copies. There are still plenty of people out there who haven't read your book. The book may not be new, but it is new to those readers. It may seem like you have spoken at every Rotary Club and bookstore in your area, but what about other nearby cities? Do you do events in other areas when you travel? Do you reach out to readers via Facebook, message boards, Twitter, bloggers, etc.? If not, you have a lot of work to do. Recently, one of the authors I work with found their best success selling their books at signings in coffee houses, after I scheduled their first coffee house event for them. "I didn't even think of approaching coffee shops," they said. Car dealerships know that people don't buy cars every week, so they are constantly looking for new customers who are in the market for a car. Think of places where you might find new readers. You can only hit up the local bookstores so many times for events.
5. They network. You won't sell books just sitting around the house. You've got to do some networking. Online networking is great, but that still isn't a replacement for good ol' face-to-face networking. If you are doing a speaking engagement, let those in attendance know that you're available to speak at other venues, too. That event could lead to several others. You never know who is in attendance.
The fact is, unless your book contains completely dated material, the only one who really knows your book isn't "new" is you (and those who have already purchased your book). Broaden your horizons, don't give up, be persistent, continue to spread the word about your book, and the early groundwork you do could lead to bigger and better things.