I'm going to do my best to do a quick description of some of the tools I know of. I am certainly not the expert so I hope that anyone using the tools will update this page as experience is gained.
- GIMP(GNU Image Manipulation Program) - Using GIMP
- It is a freely distributed piece of software for such tasks as photo retouching, image composition and image authoring. It works on many operating systems, in many languages. GIMP Windows Installer
- Blender - Using Blender
- Blender is the free open source 3D content creation suite, available for all major operating systems under the GNU General Public License. Download Blender
- Wings - Using Wings
- Wings 3D is a subdivision modeler with an user interface that is easy to use for both beginners and advanced users. Wings Windows Installer