Sex was discussed in our house, to wit: "Wait until marriage!" End of discussion
I got my information from friends and the movie 'Candy', which I snuck in at 13 with my best friend to see. (my review? 'why wasn't she drippingly soaked and sore as hell?')
I learned what to do, how to do it, etc., from the guys I had sex with.
My sisters love to talk about sex. I can take or leave the conversation, really. I'm not interested in where, how, when and how often they have sex. My mother never talked about it when we were younger and in fact, proved herself to be pretty ignorant of the workings of female anatomy when my daughter was born with a congenital condition that made her inner labia seal shut over her vagina. She asked, how does she pee then? Uh, mom...they're next to each other, not one and the same.....
I don't talk about sex much with my best friend either out of context of relationship conversation. Ironically, though, I have a few good male friends that have no problem talking sex, plumbing, etc.