Just an added note here. The last link above has lots of ideas for us and she has also asked for course for no violations of copyright. Which of course is perfectly just. So go look enjoy get all your ideas but when you make something do not sell it if you got a majority of your ideas from her link.
Her is a great gallery to get your brain spinning for color, shape, technique and other wild ideas.
http://www.thaneeya.com/sugar-skull-art.html