I am currently working with the Microsoft MVVM template and find the lack of detailed examples frustrating. The included ContactBook example shows very little Command handling and the only other example I've found is from an MSDN Magazine article where the concepts are similar but uses a slightly different approach and still lack in any complexity. Are there any decent MVVM examples that at least show basic CRUD operations and dialog/content switching?
Everyone's suggestions were really useful and I will start compiling a list of good resources
Frameworks/Templates
WPF Model-View-ViewModel Toolkit
MVVM Light Toolkit
Prism
Caliburn
Cinch
Useful Articles
Data Validation in .NET 3.5
Using a ViewModel to Provide Meaningful Validation Error Messages
Action based ViewModel and Model validation
Dialogs
Command Bindings in MVVM
More than just MVC for WPF
MVVM + Mediator Example
Application
Additional Libraries
WPF Disciples' improved Mediator Pattern implementation(I highly recommend this for applications that have more complex navigation)