Here is a full description of how to take apart one of the new iPod Shuffles.
You will a tiny philip's head screwdriver, and something thin and sharp, like a needle.
Step 1: Removing the Casing
First you have to remove the white plastic casing on the top and the bottom. Do this by prying it up with the needle. The pull the switches off the bottom side.
Step 2: Remove Screws and Metal Plates
Unscrew the two screws on each side, and pry off the metal plate on each side with the needle. Here is what you should have now.
Step 3: Pulling Out the Guts
Using the needle, pull out the guts by pushing the needle under the metal piece on the side with the headphone jack, and prying upwards. Thats it, you're done.