I am also trying to integrate the auto clavicle and scapula in my rig...... i too didn;t find some useful stuff on the internet.
I have seen devil character rig on creative crash rigged by an Indian rigger and he has used that feature in his rig.
You can study that rig.
Use maya help or google to find the utility of closestPointOnSurface Node.
Hope this link helps http://www.vfxcreator.com/tutorials/clavTut.html
You can get the desired effect by using the Auto Clavicle feature....
You can google about Auto Clavicle and still you don't get something then i will help you out!!!
This Demoreel is of Seema Gopalakrishnan...She works in Lucas Arts Singapore......She also came to India to give a lecture in CGTExpo.