This is one of the best flicks I've ever seen on this subject(currently airing on Showtime):
American Drug War (//%22http://www.americandrugwar.com/%22)
Movie Excerpt (//%22http://video.google.com/videoplay?docid=6795163243808294377&hl=en%22)
Interview with the Director (//%22http://video.google.com/videoplay?docid=8740703353227564451%22)