My guess that it is a custom molded one of a kind dash. If you look under the radio the dash is not shaped like that, that is what brings me to that conclusion. A little firberglass and some know how and anything is possible.
You could always e-mail the guy... The link on the page is pretty non-obvious, but apparently his e-mail address is firstname.lastname@example.org.
That install is very clean, but I don't like the dash either. (Personally, I like having center a/c vents, but maybe that's just me.) The pic makes that dash look kind of uneven, but I don't think the picture does it justice, though, since the car finished 10th in the 2000 IASCA World Finals. You don't do that with uneven paint.
This picture tells me that this guy knows his fiberglass, though... (or perhaps he's got an injection molder in his shop)
Hard to tell from the picture, but looks painted. The Rockford EQ sticks out a bit, so I don't think it was fiberglassed, probably just hacked up and painted. Quick easy, and as long as you don't mess up, it could look half way decent like his with little effort. I plan on doing something similiar with my future audio install, except it'd be in silver.