Original ref (for the face): http://img844.imageshack.us/img844/9295/6243madsen71662.jpg
The rest is pretty freestyled.
Used this wallpaper for the broken glass overlay: http://www.spankthellama.com/hashbrowns/main.php/d/6313-1/1920x1200+broken+glass+wallpaper.jpg
Airbrush, Dodge/Burn tool for detail and Sharpen/Blur tool for finishing touches!
Also with the help of Photoshop Skin texture brushes! Crucial tool for something like this!