Check out STM for sure. 426 Oxford St, Bondi Junction. Tell them you are from Boardworld and they will look after you. By the way, the 10% discount is an additional 10% even on sale items.
http://www.stmonline.com.au and use the promo code
boardworld when checking out.
Balmoral Boards (Narrabeen) and One Track Mind (Crows Nest) are also excellent stores. Ditto, let them know you are from Boardworld and I'm sure they will look after you.
I'd highly recommend buying the board in Australia before you go. It will be cheaper overall and you won't have to waste time shopping around for the right board. Plus your warranty will be covered in Australia.
Since you're looking for a versatile board, you might want to look for a board with a hybrid camber profile. Do you understand how rocker, camber, and hybrids work? i.e. how they affect the ride?