Save your money and make it at home: Make your own black gunpowder quickly, cheaply, and easily. You will need postassium nitrate (or KNO3), sulfur and charcoal. Remember to make this in small amounts. When making it in large amounts, is when it becomes dangerous.
From the videomaker:
Remember: You do this at your own risk. Whether done in accordance with directions or not. Also note that you will be working with explosives. Need we say it can be hazardous to your health?
Recipe for black Gunpowder:
75% Potassium Nitrate
DO NOT USE THIS IN YOUR FIREARM!!!
This video is an educational film, starring the Bush Boy, edited and produced by James Williams of Picture Rock Productions.