I discovered slash in a Dillon's in Oxford. I can't tell you which one, because this bookstore chain had five or six outlets in Oxford at the time, but I was in one, when I picked up Constance Penley's NASA/Trek. Of course, I immediately turned to the chapter on sex, and was intrigued.
So, the next time I got on the internet, I put the terms slash and Star Trek in a search engine, and I start looking around. The first things I find are some pretty silly DS9 things, but I quickly back out of that and into X-Files. The MSSS is astounding and I read the whole thing over the course of a couple of months.
That's how I found slash.
Discovering Farscape slash was, of course, all Toni's fault. I had joined the slash-writers mailing list (which I completely recommend to anyone who has the least interest in writing slash, in any fandom) when some person with the world's least pronounceable and least spellable pseudonym wrote an intro and said she wrote Farscape slash. Now, the girl I'm not dating had turned me onto Farscape, but I hadn't become a real *fan* of it at that point. It was just something I might turn on Friday nights, if I remembered, maybe. And from what I'd seen, the show wasn't all that slashy. So, I was intrigued. And I checked out the archive. Not too bad, if perhaps not all that grounded in the show's reality. And for some reason, all of the aliens had human genitals. And I told Toni (I can't remember if it was on smutscape or slash-writers) about a story idea where everyone was playing show and tell with their bodies, and Aeryn said John was icky, and D'Argo had to comfort him, and Toni said, "Cool. When are you gonna write it?"
That's where it all started. And no, you can't read the story, I ended up killing it. But it is definitely all Toni's fault.