I am sorry I plural-ed BD. Here is the site: http://www.beardeddragon.org/
What the others suggested may work too the only thing is (I am not familar with how Good Stuff feels once it hardens, is it soft or rock hard?) is would a beardie be able to gouge or scratch at your finished product. Goodstuff covered in coconut husk.
Good stuff and coconut husk with live plants works well with tree frogs, there are a few forums out there that work solely in vivarium design. They'd be able to help you more, if your need it. ALso if you google Vivarium Design you'll come across a few sites that teach you the basics of vivarium design. It's very cool. I've dreamed of babbling it in and thought it would be fun to be the person who designs zoo animal enclosures, but money is an option and schooling well...maybe some other time.