There is a wikipedia page for Cairngorm. Look at the interactive Cairngorm Explorer. Cairngormdocs.org is a site dedicated to providing documentation and learning resources. There are samples to download on this site.
Jeffry Houser has posted series on How do you learn Cairngorm. Read his 5 part series on this topic.
David Tucker has a 4 part series Flash video on the topic Getting Started with Cairngorm.
Kaushik's Blog 