You can learn how to draw objects, humans, trees and other things by learning how to sketch first. I love to sketch and hope to come home from our thanksgiving vacation with lots of new sketches to share. The movement and strokes seen in a sketch are beautiful. I like "seeing" the process, to me it shows the human element and gives the artwork authenticity. My sketch above was an exercise from the book The Creative License: Giving Yourself Permission to be the Artist you Truly Are by Danny Gregory.
I found this uber cool article on ehow about doing a sketchcrawl. What's that you say? The basic idea is wandering from place to place --with a sketchbook-- and with a single, constant goal to record everything around nonstop ... to observe, sketch and enjoy. I think I may need to take a day and do just that. How to do a SketchCrawl.