How do i model the Earth?

i posted this before but i can’t find it anywhere…how would you create Earth in blender, including the masks and cloud layers and atmospheric effects and all that other complex stuff?

The Wiki tutorial list has one listed. Here it is: http://www.uni-bonn.de/~smaeter/tutorials.php?site=planet

The rest of the tutorial list is here: http://wiki.blender.org/index.php/Tutorials/Links

Thanks very much! that really helped a lot!