The Vintage Record, Annandale
A Sydney institution for vinyl fans, located in the same strip as the famous Annandale Hotel live music venue.
Inta Music
Local online source for reissued vinyl, a New Zealand company but also ships to Australia for a very reasonable $8 flat rate.

Classic HiFi, Newtown
Well worth a visit to the south end of King St in Sydney's Newtown. Check out the 70s and 80s turntables.
Zenith Records
Want to press your own? Vinyl record manufacturing is alive and well in Melbourne.
History of the 12" single
Audiophiles and disco fans will know this story but incase you don't Wikipedia explains how the 12" single was first created by accident.
The Vinyl Revival
The press have even noticed the vinyl revival. Some examples here from The Sydney Morning Herald, Brisbane Times, ABC, stuff.co.nz