Not sure if this is what you mean but there was software called Cosmopolitan Virtual Makeover 2003 that let you do that. I think it only worked in OS 9 for mac. It's also available for the PC.
I came across a demo of an app called Change My Image a while back that'll let you chop and change your hair to your heart's content. Not really my cup of tea to be honest but I think it might be worth a look.