Here are some links for making backgrounds. They are meant for dart frogs, but can easily be modified for other animal. The easiest way is probably using Handi Foam expanding spray foam, then adding logs, fake plants, etc., then covering with moss or coconut fiber while still wet.
http://www.blackjungle.com/gallery2/...g2_itemId=2108
www.joshsfrogs.com/background.html
www.brianstropicals.com/building.html
http://www.amphibiancare.com/frogs/a...terrarium.html