Booktopia offers the best range of reading materials online in Australia! However, there is a standard flat rate of $6.95 for delivery per order. Don't fret though, from time to time, Booktopia will release free shipping offer with codes that you need to key in at checkout to enjoy it.
Alternately, when the offer expires, you can get free shipping through booko.com.au. Just search a book on booko.com.au and select Booktopia as the site you would like to purchase from. Click on the link, a pop up with free shipping notification will appear and there you go, free shipping!