Free Microsoft training
Microsoft offers some really great training for lots of products. One resource that I find especially useful to refer our clients to is the Microsoft Office Training. This resource offers over 150 short and focused lessons on just about anything related to Microsoft Office Products.
These are not training topics that most system administrators would be interested in for themselves (but they should be) but your users will love you for showing them these resources.
For more technical resources I regularly review the Microsoft On-Demand Webcast page . I review these and send links to our techs for relevant webcast topics. You can get some very beneficial information from these.
The best part is they are all FREE!