I have been working on a series of short screencasts that will teach you Windows 8 Metro Style App development in a fun and immersive way via casual gaming.  The first one covers playing music and sound effects in your Metro Style App utilizing the standard HTML5 Audio Tags and Third Party JavaScript Libraries.   

You can watch the video on Channel 9 here:

 

Slides can be downloaded here:

 

There is also a companion blog post you can read here as well as the full source code here.