wow. hours?

took me less than a minute.

just to tell you the path:

Googled "male head body proportions"
first link in results: http://en.wikipedia.org/wiki/Body_proportions
following link "heads" on that page: http://en.wikipedia.org/wiki/Head
bottom of the page, there's an image showing measurements.  clicking on the image to see it access a larger version and information about it:
http://en.wikipedia.org/wiki/File:HeadAnthropometry.JPG

hope that helps!

*edited to make links live