The principle is this. Tutorial is for Maya, but can be adapted for any other package. http://kakes3d.wordpress.com/2010/02/15/modeling-a-tree-in-maya/
WOW. Seriously. A little compensation is understandable but....I'll let you guys judge before I post what I have to. http://redtape.msnbc.com/2008/02/a-lost-laptop-a.html#posts