Here is the tutorial I've been using for Maya to help me with Dynamics. This particular one teaches how create "dents" in objects to create realistic effects on impressionable surfaces (I.E. something hitting snow.) Its really fun to play with and I'd recommend it to anyone who is just looking for a good time with Maya. Dynamics chug RAM like its nobody's business so I'd be careful before going crazy with it.
Check it here: http://www.digitaltutors.com/digital_tutors/video.php?v=534
