I am also an Aussie quilter and I have used
http://www.hancocks-paducah.com/
If you sign up for their HOP Mail, the link is at the top of the page, they send you special offers which include free shipping to Australia if you spend over $100 US and you can also buy batting, their prices shown are for 1/2 a yard so just be aware. Good service, I have never has a problem.
I recently bought from
http://www.whittlesfabrics.com/
prices are fantastic shipping can get expensive, great service I had my fabric in 6 days. PM me if you want anymore info.
Hope this helps