Ciao,
perhaps I am not focusing on anything new for anybody, but I think this video tutorial by Mike Wallace is very good and clear.
http://www.picturecorrect.com/tips/an-i ... otography/
It concerns lines, shapes and forms in composition.
I think my shots are mostly two-dimensional, this guide is very useful for me.
Then one should go through rule of thirds and golden section to have a complete view.