You can look at the female and male heads in the Image files in VV3 files in your Computer's Program files to see what looks are possible. Also, read this thread on Genetics:
http://www.ldwforums.com/ubbthreads/ubbthreads.php/ubb/showflat/Number/132603/page/1#Post132603
But if you'd rather be surprised by the hair colors or figure out how it works on your own, then don't look at either.