I have to make a zombie wedding cake and they want the figurines to look as close to real people .as possible 

I recently came across this one but haven't yet tried doing it this way.  It is for a pregnant woman but you will get the general idea  This is in 2 parts:http://www.youtube.com/watch?v=g8qEBL2aXOI

and this is for the male:

Good luck.  Hope this helps

I've pinned a lot of tutorials on my Pinterest board. There are a lot on figurines.  http://pinterest.com/sweetgrace/tutorials/

Thank you PinkLisa, you have sooo much tutorials that are very useful. I am following you on pintercrest.