Did you know that Microsoft has MVPs?  Individuals that are masters of the universe in terms of specific software platforms and their functionality, such as Microsoft Word, Excel, PowerPoint, Visio, etc.  I found these resources very helpful in learning tips and tricks or for training purposes.  I have either followed their newsletters, or many have yahoo groups that they moderate (part of the MVP criteria).  I have been very impressed with this resource, MouseTrax, an MVP for Microsoft Word:

http://www.mousetrax.com/TechTrax.asp

You can find other Microsoft MVPs at the MVP Community:

https://mvp.support.microsoft.com/communities/mvp.aspx