Love these guys. Where I used to live I had Spring Peepers that would come out and lay eggs in my ponds. They sounded like heaven in the spring. I missed them so much when I moved that a friend bought me a Swarovski crystal tree frog. It was a wonderful present but I can't get it to peep. In Puerto Rico the little tree frog called Coqui (from the sound it makes) sings all night long, they are tiny little things but make a real concert every night.
I keep toads in a vivarium but they don't sing for me. I think they need a girlfriend.