Have just experienced one of those moments of pure dread when I read this thread.
It stated above that you have to print off and send with the visa application, form 80 which is the character assessment which I haven't sent with mine.
Have just checked in Immi website and you only have to send it when requested if you are outside of Australia.
Cut and pasted for ref:
For the Australian Government to determine whether you are of good character, you may be asked to provide police certificates for each country you have lived in for 12 months or more over the last ten (10) years since turning 16.
If you are applying outside Australia, you do not have to provide this information when you apply. You will be advised when it is required.
If you are applying in Australia, you should provide this information with your application.
Hope you don't mind me correcting you !!
Joanne x