Yes, especially at Wal-Mart, Target, Joann Fabrics, the Flower Factory, Bed Bath & Beyond, and other department stores! You can find tons online as well - my friend did frogs!
I saw seen a couple of frog-themed bathroom decors, so I am sure you will find some. There is a lot of animal-themed bathroom decor, fish-themed ones are the most popular ones of course. My parents have a dolphin-themed bathroom in their new house.
A lot of online stores carry frog themed bath decor. I have a shower head that is a frog. Large stores like bed bath and beyond tend to carry cute themes like this.
While you may have to spend time looking at a variety of stores and internet sites you should be able to find enough frog themed decor to fill out your bathroom's overall look. You may have to use items that portray other animals or themes as well to get frogs.
