My two most recent tutorials (as of this writing).
1.) How to Create Realistic Rocks in Blender - http://www.benamend.com/2011/06/14/how-to-create-realistic-rocks-in-blender/
2.) How to Create a Sand Material in Blender - http://www.benamend.com/2011/06/15/how-to-create-a-sand-material-in-blender/
