Here is a super cheap deal for the Entertainment book. There is still plenty of time to use the coupons as they are good until the end of the year. The book for my area cost $17.50 (reg. price $36) but some areas are as low as $15.
Other people have also recommended buying one for the area you plan to go on vacation this summer. For instance if you plan on vacationing in Orlando, you could buy the book for that area and save way more than the $15 you spent for the book on attractions, food, and entertainment.