How can i buy barbiturate sleeping pills without prescription.?

I have severe insomnia and OTC sleeping pills are not working for me. I heard that prescription sleeping pills work better, but are hard to attain these days. My family doctor is not willing to write a prescription pill and told me to find other ways to help me fall asleep. And I have tired EVERYTHING…OTC pills, exercising, reading, etc. Can someone tell me how i can get barbiturate pills, so i can fall asleep quickly rather than laying in bed for hours.