How to Create Your Own Textures in the Open Source 3D Program Blender
Just because software is free, does not mean you can't get incredible results out of it. Blender is a free 3D program that has a ton of capabilities, and it has helped create a few movies so far, including the completely open source live action film Tears of Steel. If you've done a bit of 3D work (or if you're brand new to the 3D world), and you've wanted to create some of your own textures, the tutorial below from Cgtuts+ can help you get started.
Here's a preview of the tutorial:
Be sure to head on over to Cgtuts+ for more excellent tutorials that can help you get started working in 3D.