Although my Clothing Catalog will help you dress NPCs more quickly, what about their choosing their faces? This handy 'Heads Catalog' may save some time by letting you see what all the faces and hair styles look like before selecting the appropriate one for your NPC.
RedwoodTreeSprite was good enough to capture screenshots of all the standard Morrowind heads. I've added images of the various hair styles and assembled them into a thumbnail reference. Here are some reduced-size samples of the catalog's pages:
The guide includes both the normal style NPC heads and their vampire equivalents. One moderately useless factoid: given the wide variety of heads and hair styles available, in theory it is possible to create 1386 unique NPCs. And that's not including vampires.
You can download a copy of the catalog from here and check for yourself. It's a 1.96MB zip file with the PDF document inside.
You may also wish to visit RedwoodTreeSprite's site for more excellent modders' resources, plus links to many free tools.