I found some research on the average face shapes for both male and female, which was useful for generating a head to paste photographs onto.
Constructed out of 32 different male faces.
Constructed out of 64 different female faces.
I've made a FaceGen out of the male face, and imported it into ZBrush, ready to paste some textures of familiar faces onto it using the spotlight feature.
What the character should look like pieced together in UDK.
After not knowing about using normal maps for detail, dividing the character's geometry way too much, exporting over the original and saving in Maya ending up with roughly a kajillion polys, I had to go back a few steps. This is the model in ZBrush right now.
Going to add a little more detail, then get painting.