http://www.wingfox.com/f/f-8307/

The tutorial is an excellent overview of how to approach an illustration from start to end. It will take you from designing the character with silhouette all the way to polishing and fine-tuning of the finished illustration.  Aside from the overview process of my approach to character design and illustration, the tutorial covers as much information about material, lighting, and rendering as possible, as it takes you through different stages of the illustration.