Ambien is a prescription only drug so I doubt any providers would offer it. Plus Ambien affects different people different ways. Some people fall asleep within minutes of taking it and some people can have wild, freaky sex on it. Problem is, the person taking the Ambien may not remember the wild sex and if I am paying for sex, I really want to remember it!
I doubt any provider would offer this. The risk is not worth it. I would recommend going to your doctor and see if he will give you a script. Then take it and rub one out and see what you think. What if you pass out don't wake up for 3 or 4 hours. She's going to leave and you'll wake up with blue balls.