Where do bi guys find MMF threesomes with attractive younger bi couples?

Well, Im a studmuffin. I dont want to sleep with older people or overweight people, and thats all I get on Craigslist. I mean, I'm VERY in shape(6 pack, muscular), and no tattoos, piercings, etc.. and am clean cut looking. the only porn I maturbate to is MMF and I fantasize about sharing a woman with a guy friend of mine, feeling his dick slide into her vagina with me, feeling it rub on mine, and feeling him cum . Its just so hot. I just dont know where to start and am scared honestly because I dont want to be judged/shamed by society (even though i was an outcast my whole life)