I started in High School, 1976, in my second year. One of the guys in the SF club found a new game and a bunch of us just had to find it. Soon I had the white box set in hand and we were on our way. Soon after came Greyhawk and the idea of different damage by weapon of creature as well as a new model for XP. This set, along with Blackmoor, Deities and Demigods and materials from the Judges Guild kept us going. Even with moving to a differnt school I was able to continue playing through graduation.
Next move was to the US Army in 1978. I picked up the AD&D Players Handbook and Monster Manual off post (The US Cavalry Store near Fort Knox KY) and even managed a game while in Basic Training. After Basic I was sent to Germany (Mannheim) and soon found a DnD group. I was with this group for 2 years and we palyed many LONG sessions (typical was starting on a Friday @ 6PM and going until Sunday @ 3PM, yes LOTS of Caffeine). This group was one of the best I ever played in, and included someone destined to DnD greatness. The group dynmaic was great, we usually had 4-6 players and had many EPIC adventures. One of the nice things with this group as the interaction and team spirit of the players. Maybe it had to do with the types of soldiers we were, maybe just the time and place.
After Germany I was sent to Georgia (Fort Benning). I found a group but only played about 3 sessions. This group was "all about me" and were quick to stab each other in the back and loot the bodies. The next table over was guys playing Napoleonics, and well that was more fun for the next couple of years.
I fell away from DnD for the next 20 years. I kept my books but I did not play or actively seek a group. When 3.x rolled out I went ahaed and bought the books as I now had rasied a group of my own. This still had not jelled into an on going event until this last summer when I "bit the bullet" and bought the 4e set.
Since this summer we have played at least once a month and are trying to schedule every 2 weeks. I'm back in my role as DM (though I'm trying to train a couple more) and we are having FUN.