This is a simplified version of snapface (http://code.google.com/p/android-playground-erdao/wiki/SnapFace).
It could serve as a starting point if all you want to do is integrate the android hardware camera with the android face detect api.
Download the source. Run it and place the camera in portrait mode about 15-30 centimeters away from your face. Once the camera detects your face a new activity will be launched.
This currently only uses rear facing camera and I haveo only tested it on motorolly milestone.
It only seems to work in landscape for some reason.