PS:  This is not to say that sites won't have copyright disclaimers, they more or less have to in order to protect their butts, but it really is a matter of, "who the heck is gonig to know one way or the other??"  So, it's sort of impossible to enforce.

Having said that, there are several good sources for flags generally, including:

http://www.crwflags.com/fotw/flags/

http://en.wikipedia.org/wiki/List_of_sovereign_states#A

And specifically, the flags of Australia at: 

http://www.theodora.com/flags/australia_flag.html

Ricky

Could be worse, could be raining.