Attached Link: http://homepage.mac.com/kflach

Actually you can change the keyframe interpolation to "linear" and it will stay steady. There's another one too that makes the keyframes white - I can't remember it off the top of my head. One note though. No one ever holds their head completely 100% still. If you're going for realism sometimes you can just set a keyframe after the head "stop" that reduces the motion but adds an element of "randomness" - a *very* small motion. It makes it look more natural. Check out Guido (the hero) in "dude, you suck" via the link or check out little-dragons Sabrina animations (you'll have to search by his name to find threads he's posted in). QuickTime required for my stuff at the link.

Before they made me they broke the mold!
http://home.roadrunner.com/~kflach/