Well, living in Southern California my whole life, I went to Disneyland often (even though I don't really remember it).
I rode my first coaster when I was three (Little Dipper at Castle Amusement Park) and really liked it; I remember riding it over-and-over.
When I was four I was forced to ride Big Thunder Mountain Railroad at Disneyland because according to my parent's it was just a "choo-choo train". I hated it.
For several more years I was forced on rides and hated all of them (Pirates of the Carribean, Pteranodon Flyers at IOA, Mulholland Madness, etc.) although as I got older, even though I was still scared of coasters, I loved going to parks! I remember visiting SFMM and KBF in 2006 and not riding one ride, not even kiddie coasters or log rides, but still having a lot of fun. I was fascinated by how big the coasters were, and I could watch and take pictures of them for hours (and I did).
Eventually, after a couple more years of doing this, in March of 2008 I went on a "mini-trip" to Northern California to visit family and go to CGA, SFDK, SCBB, and GG. I rode the kiddie/family coasters at all of the parks and the log rides.
I slowly eased my way into coasters, by then riding rides like Revolution and Ninja, and then Viper, Batman and Scream, and then Tatsu and Riddler's, etc. Now I will ride any coaster (unless it spins rapidly).
So, really, I've been "in to" coasters for a while now. I think I started looking up/learning about roller coasters around 2007 and I joined my first forums in 2008.
By the way, at the beginning of last year, my coaster-count was 7. Now it's 126.