Here you'll some basic, "getting started" tutorials.

Basic

1. Getting Started, Part I - Materials
   
2. Getting Started, Part II - Sun & Sky
   
3. Getting Started, Part III - Rendering
   

We also have tutorials in:

Spanish

1. Guía rápida Parte 1 - Materiales
   
2. Guía rápida Parte 2 - Sol y Cielo
   
3. Guía rápida Parte 3 - Renderizando
   

Japanese

1.  Getting Started, Part I - Materials
   
2. Getting Started, Part II - Sun & Sky
   
3. Getting Started, Part III - Rendering