I'd say I was just a young chap when it became clear that I love tickling. If I had to guess, roughly 8 years old would be when it hit me. Obviously at that time it wasn't a sexual thing (although it clearly was a precursor to something sexual). I distinctly remember two incidents at the same summer camp that solidified the idea in my mind ... the first memory was at this camp, they had people ranging from 6 or 7 years old to probably 15 or 16 ... I was sitting around minding my business when i heard some laughter and naturally my ears perked up ... I looked over to see three people really going at this young girl (who, ironically, I tickled years later ... a story for another time). They were just playfully tickling her, because it was common knowledge that this girl was (is) insanely ticklish. I distinctly remember hearing one of them say, "her stomach's wide open" and I thought I was going to die.
The second memory I have, from the same place, was just playful tickling I did back and forth with this girl named Sherri ... I don't quite remember if it was the same summer that I witnessed the tickling of the other girl ... but me and Sherri used to playfully tickle each other all the time. It was not flirtatious because I was 8 and she was 9 ... or maybe it was early flirting ... but it was fun as hell ... and thinking back on it, she could very well me a member here right now ...
Those two memories are my first realization that I love tickling ... it became clearly sexual later on ... I also remember some of the same sites that people have mentioned. I used to sneak to SWTickle after school when nobody was around ... and look at pictures of dorothy lane in stocks, cory lane's feet, and the hot realtickling maid who gets her feet tickled. Ahhhhh the good old days