What a coincidence. I too am in need of ideas for mossy frogs. The problem is that everyone sets them up very differently. My current idea is do make a background with clay or the spray on stuff (I can't think of the noun) and construct an island in the middle of the tank, surrounded by water. I'll place plants on the background, and on the add moss and plants on the island over the substrate. as for the water, I'll have some aquatic ferns and pothos.
What I do need is a suggestion or two for putting in a filter/ water pump...