software links

Here are some links that might be helpful:

First of all, the google directory here

Then colorspace and photoshop plug-ins here, here and here. An image analysis software list.
Also, generally speaking about free software, blender and inkscape are very good solutions, and two last links that you might need later on when we move into 3 dimentions: isosurf and sculpture generator.
Keep in mind that those are just examples. You can find much more things in relation to what you are doing... and if you do, you can post the links here.