Just type in "Titan billet grille" in Google. You'll get about 120,000 sites that sell them. Or, pick up a Sport Truckin' magazine or most other truck mags and the adds are full of them. I have a catalog from DriverFx (who also has a website) that carries hundreds of brands of accessories for trucks and cars. That's how I found my powdercoated black tube grilles. Trust me, you can't swing a dead Dodge Ram without hitting a site that sells them for the Titan. Happy hunting!
Oh, and don't forget about the Titan Talk supporting vendors. You can find a lot of Titan parts by clicking on any of the vendor sites listed at the bottom of the forum home page.
Not to mention, look at the bottom of this thread.