Every book proposal requires research into your field. I’m currently researching a nonfiction book proposal on volunteers, and I have found Amazon.com extremely helpful. A few key word searches have provided a broad array of books in my field. Once I have a list of potential competitors for the market, the hard work of reviewing these books and differentiating them from my own book begins.
Fortunately Amazon provides a number of simple ways to learn about books without necessarily having to purchase and buy every potential competitor.
Search inside the book
A search inside the book yields the crucial summaries provided on back covers and inside flaps, the table of contents, and a few pages of the introduction. This will give you a great summary of the work as well as some key specifics.
Publisher’s Weekly and other reviews
Test your understanding of the book against the reviews typically placed below the publisher’s information (date of publication, press name, ISBN number, etc.). If not Publisher’s Weekly, many books will have brief summaries provided from reviews. Pay careful attention to the source of the review to ensure it’s as reliable as possible. Take the publisher’s summary with a grain of salt since their goal is to convince you to purchase the book.
The list of related books.
As you scroll down the page you’ll notice a relatively new feature that allows you to browse over 50 related books. This can save you a lot of time in your research. My advice is to try and find the book most like your own, and then look into the related books on its Amazon page.
Customer reviews can be hit or miss, but they’re well worth reading because you may come across a few stating, “I thought this book would be about _________, but instead it’s about _______.” These are solid gold for your purposes and will help you narrow down whether or not this book is worth comparing to your own.
Buy the Book (used if you can)
If you still feel a bit uneasy about the book you’re browsing, it may well be worth purchasing it just to be sure you’re not saying the same exact thing. I have done this in the past and it was well worth the peace of mind. I also made some clear and effective distinctions between the competition and my own work. You can always sell it used after you’re done with it to minimize your cost to a few dollars.