There a shop in Australia by the name of Jaycar pretty sure they are in NZ as well they took the whole electronics market from Dick Smith and Tandy some years ago.
They are a good outlet to buy many things but they are only allowed to give advice, company policy. Then there is Middies a sort of commercial industrial electrical shop Australia wide i sought help from them while buying couple of power appliancse for the HDR. But openly they cant build anything for you maybe in private consultations (unsure) id assume its like that in most companies these days.