You're probably correct, they are most likely Polypedates dennysi. They have been appearing more and more in the hobby, and are really the only "blue" species that I can think of. For photos check the Kingsnake classifieds. I don't have any that I can post.
I don't think they are very difficult captives, probably comparable to any other tree frog species. They would probably do fine in a temperate vivarium with normal temperatures. I think that the only catch with these guys might be that they are fragile when young, which is really true with any species. To look for more information broaden your search to any foam-nesting tree frog, but like I said, the care is pretty basic.
I just picked up one of these myself. A very nice frog indeed...
here is a shot of the temp set up. Mimic'd a green tree set up and that link up there as well... Just need to do some fine tuning with temperatures since its been cold here lately and the hubby is still crazy with the air cond.
My axie is acting woerd he was a rescue as stated in a different post he got better and now seems to be deteriorating again...again all tank conditions are OK and as should be. He seems to have some black dapple like pattern under his bottom lip? Is that normal? And his two back feet have a little wierd growth? Almost? Tiny tiny tiny lump. His capillaries in his feathers also appear darker and more visible. Any help would be appreciated