There is not a whole lot of information on the web about raising a spring peeper in captivity, partly because they generally don't do well. If you read my blog entry that I have on here, you can get some ideas about the housing. Mine are tiny babies right now, so I'm a little more confident that they will do well, considering they spent very little time in the wild.
If it is an adult, I would probably get a 10 gallon tank. They like to use both the ground and the trees, so make sure you have a lot of leaf litter (that is where they hide and forage) along with branches for them to climb. My peepers do love my bromeliad.
They need small foods, either tiny crickets or fruit flies. Even the largest of my peepers (who is large enough to chirp) eats very small food items.
The water dish is very shallow, like 1/4 inch. But that's because I have very tiny froglets in there along with the bigger ones.
Go ahead and read my blog, I put a lot more detailed information about what I'm doing with them in there. You can also read the Pacific Chorus Frog care sheet as they are very similar.