[wagonman76]

For my airdam I drilled small holes into the underside of the valence, where one would never see them unless they jacked up the car and got their head straight under there (bad idea anyway).

You should be able to attach to something on the frame under the front of the car. You could also attach to the radiator support or bumper support, between the hood and headlights, or through the grille (take the grille right out). You could come around to the sides and attach using the fasteners that hold the wheelwell liners to the fenders.