Go Game Guru: has the biggest range of Go equipment and books in Australia, at the best prices. They ship orders to Australia and New Zealand from Sydney and Canberra and you can contact them for local pickup too. NOW CLOSED
John Hardy has an online shop based in Brisbane. It is not e-commerce enabled though, so you have to order by email, phone, or mail.
Mind Games Australia, has stores in most capital cities.
PacifiGo: based in Brisbane, posts around Australia and allows local pickup.