Now the best part: pimp it out, it's an arcade stand and it have to look colourful and a bit of stupid ;P I really had no time so I added a smile stic...
I've previously seen arcade-like stands for orginal gameboy, and psp ( [http://com/2008/03/quite-possibly-the-moste-useless-yet-awesome-psp-accessory-ever/ to view this psp one clik here] ). When I saw this PSP one few hours ago i kept myself looking for ds one (because it would be cooler to play some of touch screen games), but i found nothing-so I made one myself.
The first thing you have to make is a good project- the easiest way (which I've choosen) was to put ds sideway while it was open on a sheet of paper and then i drew the outlines of DS's back (making the lines as straight as I could). That gaves us the DS's holder (from side-view). Now you have to add some lines to make it an example of side-wall of our arcade stand (keep in mind that the DS's holder should be in a position to make LCD viewable). If it doesn't look good or It does not give you satisfaction, do this step again.
Step 2: Making the project on a cardboard
Now you have to draw your side wall project on sort of a big cardboard, and draw the back wall and flipped side wall (and other walls that will be in front and at the top/bottom). On the picture there is a little help for you about building arcade stands/machines for newbies (this is the simpliest example of how-to-make-one, it's not precise but fast ;). In our arcade stand The X lengh is about 9cm (it's because the DS's sides will be sticking out for more usable L & R buttons), and the Y lengh is your personal thing ;)