There are a few toon shaders that come free with Poser 6.  Look in the Sixus 1 folder under the material tab in your Poser 6 directory (I think that they are meant to go with the Alphaman / Betaboy character).  I like how they pick up contours and shading, though the outline is rather uninviting, in my opinion.  The colours are limited, but these are easy to change.  You may want to experiment with these in addition to the free ones you found.  And good luck!