It says on the page that I got it from havoscope, webehigh and googling different sources like UN drug reports and newspaper articles. Furthermore I fully admit that the prices are approximations, I don't trust any of these sources to be fully accurate. I want people to TELL ME how much the drugs cost in different places and I'll update the map so that the prices are correct. I only listed cocaine, marijuana and ecstasy because these three drugs alone make up a large part of the drug economy and culture and I don't particularly want to document the price of more anti-social drugs like crystal meth or heroin.