I have been exchanging mail with Bill Konrad about how we can improve the Facebook Developer Toolkit work that we put together.  It's been a popular, skunkworks project to help make it easier to target Facebook development using .NET.

He put together this awesome article on how to get started:

http://devtacular.com/articles/bkonrad/how-to-use-the-facebook-developer-toolkit-20/

The great aspect of this project is that it's under our OSI Approved MS-PL license.  So get involved, help make it better.