I live in Belgium, and it's hard to find a decent magic shop here, let alone find one that sells supplies at a decent price. So I had to go looking for other ways to obtain fanning powder.
Go to your local pharmacist and ask for the chemical compound "Zinc stearate". If they don't have it they will probably be able to order it for you. Not only is it alot cheaper, it's easier than buying online. (also see
http://en.wikipedia.org/wiki/Zinc_stearate ). If you are unsure on how much to buy, 50 grams goes a really long way.