There aren’t any shampoos that will make your hair more wavy, only shampoos that will aid in keeping your curls healthy and manageable. However, there are THOUSANDS of products out there that will do the trick. I’m a huge fan of TIGI’S Curlesque line. There are all types of sprays, serums and molding creams that will give your hair that extra wave you want. There is also an excellent Sea Salt Spray that really rocks.
I would also check out Pureology and Bumble and Bumble. They have excellent products for that “just got back from the beach” wave that’s really in right now.
Hope this helps! Let me know if there is anything else I can do for ya.