Ribbon Screencast using Visual Studio 2008 Ribbon Designer
There's a nice screencast to check out that shows how to use the Ribbon designer and use built in Office icons in your ribbon:
http://channel9.msdn.com/ShowPost.aspx?PostID=345898#345898
Also on the topic of ribbons and icons, check out this great post at Andrew Whitechapel's blog on using transparency when grabbing Office icons for your .NET app:
Preserving the alpha channel when converting images
