So you want to know how to create 3D models in a 3D program? Is there some specific program that you need help with? You can find plenty of good tutorials for different 3D programs with Google: https://www.google.ee/search?q=3d+tutorials
If you just want to create some effect in Photoshop, then could you show us a sample (perhaps some other photo from Google) of the effect that you would like to see?
You can sort of do this, but it'll always be more of a face-shaped mask than a full 3d model of a head.
There's an After Effects plugin called Pixel Cloud which separates every pixel in an image and displaces them in z-space using a depth matte. I've done it a couple of times, it's a bit of a fiddle but it does work. Unfortunately it needs to be quite subtle or else you'll start to see the gaps between the pixels, but it will give you noticeable 'depth'.
There's a tutorial here: http://www.youtube.com/watch?v=QGEtGhiVQ7g and the plugin is available at aescripts.com