A few days ago I was reading through some stuff when I ran across this from Halie Satanus. He is using a program called Facegen to make new portraits, but as he says in that thread there are only two hairstyles available on the free version, which limits what you can do.
I ran across some generic hairstyles that someone made for the Elder Scrolls game. You cannot use them with Facegen, but you can export the Facegen as an image and then resize these and layer them over the top. It works fairly well.
These are all the same face, with different hairstyles layered on top. There are 157 different files in this package.