This video shows how to make rootbeer from scratch using natural ingredients. Without the use of extracts. NO EXTRACTS!
You can find your ingredients online and in most home-brew shops.
I usually get the stuff I can't pick myself at the following stores:
You can carbonate with yeast or force carbonation with CO2 at 30 psi. Yeast carbonation taste better and it is how carbonation was originally done before the mass production of soda pop.
Root Beer Rag Performed by Owen: http://www.youtube.com/watch?v=UmmM3wnQ9WU&