I thought I would try and help you out as I am from Sydney. Please let me know if you need anything else. Hope this helps!! :):)
Hottest restaurants: The Winery (Surry Hills / Darlinghurst), Quay Restaraunt (Circular Quay), Glebe Point Diner (Glebe), Strangers with Candy (Surry Hills), Caffe Sicilia (Surry Hills). These are all restaurants that are my favourite. But if you go onto Urban Spoon Sydney you can find heaps of good reviews.
Clubs: The Ivy (George Street), 21 (Kings Cross), Kid’n’Caboodle (Kings Cross), White Revolver (Bondi), The Backroom (Kings Cross) – There is heaps more but I just cant think of any more at the moment lol.
Hotels:The Observatory Hotel, Intercontinental, The West Inn, Sheraton on the Park, Park Hyatt Sydney, The Darling Hotel. (There are plenty more! You can just google Luxury Sydney Hotels)
fashion/art/design: Sass n Bide, Ksubi, General Pants Co, Sportsgirl. These are jsut some of our main stream stores, but there is alot of small quirky and vintage stores around Newtown, Surry Hills, Paddington and Bondi. As well as there is Glebe Point Markets, Surry Hills Markets, Paddington Markets + Rozelle Markets which all sell quirky clothes + other little antique and vintage nicnaks.
Art: MCA is one of our main Art Galleries, but we also have other small galeries in and around Sydney in Paddington and Surry Hills. We always have events on like at the moment we have the Biennale 2012 on which is all of Sydney and on Cockatoo Island.
I hope this helps you a little bit, you can just google alot of places or magazines such a Monster Children, YEN, Frankie, Oyster and they will also show you fashion, art, and Design.