Introduction to Prism for WPF, by Brian Lagunas, is a Pluralsight course that covers how to use Prism, a MVVM library for WPF.
The course is not very long (about 4 hours), and it covers the basics of how to use Prism quite well. Examples are simple and to the point.
Prism is much, much better than using raw MVVM, as it takes a lot less code do the same, leaving your code much clearer and more concise.
However, my standard comparison point is DevExpress.MVVM, which is also free, but which I already have paid support in my regular component subscription with them. Plus, they manage to require even less code, and have many cool features.
Overall, recommended if you are interested in Prism. But you might want to take a look at DevExpress' library, too.