To get the Messenger buddy list of a user, try looking into the Contacts Control. You cannot (as far as I know) strip all addresses from it (also known as "scraping"), but you can make your application interact with it.
Danny Thorpe has an excellent blog detailing what you can do with it (and often how, as well).
It's the best thing next to writing an application to log in to the Messenger servers directly (which is not allowed, and its unrecommended).
Monday, December 18, 2006 2:52 PM
Microsoft is conducting an online survey to understand your opinion of the Msdn Web site. If you choose to participate, the online survey will be presented to you when you leave the Msdn Web site.