Try looking up Peter Breggin. He wrote a ton of great stuff. I strongly oppose his stand on certain moral and ethical issues (the things he said about treatment of abused children), but his work on over-prescription of meds is unimpeachable as far as I know. There's also a book called The Antidepressant Solution by Joseph Glenmullen. I think they're both psychiatrists, so, highly credible. Then there's a book called And They Call It Help by Louise Armstrong, which is specifically an exposé of the drug industry as a moneymaking machine. Good luck on your paper.