Well, MSN may be different than the others in how it determines localization. To use this technique, do Yahoo searches like this:
That picks out all links to example.com coming from Canada and the UK.
Having said that, I agree with kichus: The Google sitemaps blog spelled it very specifically:
All this is doable with a tool... Gimme a shout if you want me to write something like this for you. I'm quite affordable
If you want your site to show up for country-restricted searches, make sure it uses a country-specific domain (such as www.example.com.br)
. If you use a domain that isn't country specific (such as .com), make sure that the IP address of the site is located in that country.