As in every purchase, you need to look around and find one that suits you. Some variables are frequency of use, age of rider, accessories on the bike, security systems, where its garaged and so on. As streak has said, there's suncorp, and also insure my ride, swann, qbe, aami, Shannons and many more.
http://www.netrider.net.au/forums/showthread.php?t=81190Shop around and find the one that fits you, your budget and your bike.
Cheers
Sab