I had just started high school, and my family had moved to a smaller town, which was kind of depressing. I had been listening to classical music for a couple years and I knew that I would miss having a well-stocked public library nearby.
On PBS I watched a performance of M1, and the third movement struck me like a thunderbolt. I loved how it was simultaneously serious and satiric, and from that moment I could recognize Mahler's music almost instantly.
I bought M1 with Adrian Boult and the Vienna Symphony (not the Phil), on Vanguard I think, and began acquiring other symphonies as meager proceeds from delivering newspapers would allow. I remember having M3 and M9 with Abravanel, and later, M9 with Walter/Columbia, a recording I liked much better, though it would be a few more years before I really understood the music.
One day I turned on WFMT in the middle of M6. After about two notes I said to myself, This is Mahler, and this is my favorite of all I've heard so far.
I attended a small college in Iowa, and one of the benefits of it being a small school was that I walked into the radio station offering my services for anything classical, and was immediately anointed the Classical Director. The faculty advisor was a Mahler enthusiast, and the station manager explained, "If you go to Bob with a purchase order, make sure you include some Mahler and he will sign it immediately." True enough! (Bob is a great guy, we became good friends, and he's one of the last teachers I knew there who's still around. We keep in touch.)
A bit OT, Prokofiev was another of my early enthusiasms, and each time I revisit his music, my estimation of his greatness rises. Last weekend I picked up a copy of "Cinderella" complete on two MHS LPs with Rozhdestvensky and the Moscow Radio Symphony. The discs are fine pressings in miraculously good condition, the performance is outstanding, the sound is way above average for Soviet-era recordings, and the intelligent, perceptive liner notes by David J. Rabinowitz are a blooming miracle.