I’m just about to expand my knowledge a bit around App-V. I haven’t done any hands-on yet, because I usually first focus on gathering all the useful resources available on the net, and then start reading these. By doing so, I found these fantastic videos on The Blogcast Repository.
Deployment Scenarios with App-V 4.5
Planning Considerations before Implementing App-V 4.5
The App-V Client (part 1)
The App-V Client Part 2- Deep Dive
By the way, if you are not familiar with The Blogcast Repository but like video based trainings, have a look at the Repository, there is lots of other Microsoft related Technology training material there.