tedster - 7:49 am on Sep 6, 2010 (gmt 0)
Let's take those in reverse order. If you have a country code TLD, then you do not have the option in Webmaster Tools to target a different country. So .com.au is stuck with Australia, and .co.in is stuck with India.
I think that answers your first question, too. Even if you have "location" in the page title and in all the usual spots, a .com.au domain will have a tough time ranking outside Australia.