Keyword research tools - It all starts with good keywords.
Firstly, emphasis is on the Google keywoord generator, that will produce a large amount of keywords but without exact number count.
Yahoo keyword tool on page 3 of the sign up process, just skip to page 3 use the tool to research some keywords and associated searches.
Since the US and AUS keyword usage is deemed to be very similar, you can use the US tools available with this smart software download called Good Keywords. It's a smart little tool, have it sitting on your desktop for frequent use will help you finetune your campaigns.