This is a project me and a friend did quite a while ago. We simply printed a picture off of the Internet, traced it onto the *outside* of the case, flipped it over and routed out the inside with a dremele with a routing attatchent and router bit. You can easily edge light this using a few LED's, and even make it sound activated (which I plan on doing soon) quite simply using some of the other guides on Instructables. One thing to note is that it's important to do the etching on the inside of the case so that the outside is smooth and the direction of the etch affects the light when edge lit quite a bit too.
Sorry for all of the instructables with only finished products and no step-by-step pictures/instructions. These are all old projects I did and I didn't take pictures throughtout. The next project I do, I will document it much better than these ;)