Microsoft's Ken Henderson hosted a web cast called “Introducing Notification Services in SQL Server 2005”. It was recorded three years, but it’s still a great material. If you’ve ever sat in on one of his sessions at PASS, you know he’s a great presenter.
Of course much to my and other's chagrin, SQL Server Notification Services is not part of the SQL Server 2008 product. Perhaps that will become the fodder for another post.
In the meantime, enjoy the web cast!