The books expire Nov 1 each year. They are designed to be fundraisers for nonprofit groups, We start selling ours in September. There should be a "local" office for Entertainment near you because they are the ones who solicit the merchants to participate. They can tell you exactly when your book will be available and even point you to a local non profit group you might want to support at no additional cost to you.
Here I just look up ENTERTAINMENT in the white pages and there is a listing. Also, in the front of your book there should be a phone number.
And for everyone who has a book I urge you to have "registered" it by filling out the info in the book and submitting it. That way you can find out about new merchants who sign on after the book is printed.