You can definitely use Poser, but it would be better to use some type of paint program in conjunction with it.

some things that may interest you are:

NearMe:
http://www.contentparadise.com/productdetails.aspx?id=9885

Toon Shaders:
http://www.runtimedna.com/Olivier/

i think there are even toon shaders you can get here too.

http://www.renderosity.com/mod/bcs/index.php?ViewProduct=71662&keyword=toon+shaders

There are also free toon shaders that you can find on the internet.