None of the search engines provide any information on how to be listed in results when searching for "only in <region>"

How can any search engine be expected to return your example when looking for sites "only in Australia" - it is a .com site hosted in Canada ---

Most search engines appear to use some sort of algorithm primarily based on country of server location and top level domain. In Google server location appeas to carry more weight. I have not taken time to look at how MSN do it.

If you want to be listed in "Australia" use a .au TLD and have the site hosted in Australia --

CBP