I usually don’t run specific ads on my sites - however Amazon Prime is a different matter. Once signed up you can rent books from the Amazon library for free. All of my books are part of this deal and I encourage you to check it out. Usually the free books do not get advertised enough as they are just a small part of the overall deal - but to me they are the most interesting of all the benefits you get with Amazon Prime (free shipping, instant acess to Movies and TV Shows etc.).
So check it out here - might be worth it for you (especially there is nothing you can do wrong with the 30 day trial):