If you would like to buy and sell physical gold without the risk of shopping at rogue retailers you should have a look at ETFS Metal Securities Australia Limited.
This company allows you to own and trade physical gold bullion through a listed security traded on the ASX. The real gold you are trading is stored in a vault somewhere in London and I believe it is also backed and guaranteed by the Australian Federal Government
ASX:GOLD
Otherwise, if you wish to hold in your hand Perth Mint would be your safest bet
