I don't know of any specific laws relating to Asian House Geckos, but i would have thought it would be illegal to keep an introduced pest as a pet such as with Red-Eared Sliders. Perhaps someone from QLD can clarify.
As far as I am aware (and this was told to me by a NPWS worker) the only reptile allowed to be kept in Queensland without a licence is the Asian House Gecko. The only real place to get one would be to catch it.
Difference with the red eared slider is that it is regarded as noxious. I think NPW have pretty much come to terms with the fact that the Asian House Gecko is here to stay. They are found from 1 end of the state to the other now and so far have restricted themselves to human habitation. Time will tell if it stays that way.
I wish they weren't here as then it would be more likely to get Natives around the house. I get loads of AHG's at my place and the occassional Robust gecko. The Robust's are generally larger and push the AHG's around when they are present but I don't know if the fact that there are AHG's means they don't visit as often?
A call to NP in Queensland would get you the right information with regards to keeping an Asian House Gecko.
Ill bet your from Cairns or somewhere around that area.When I was there the place was swimming with these guys. I don't think you need a licence for them but not sure. There is that many of them up there it would be silly to need a licence.