Hmm, good question. I must be getting old also, I don't remember the year (whatever year it came out) nor the type of machine I played it on (probably an early IBM but possibly a C-64/128). I've played Civ I, II and now of course III, Colonization, MOO, and a host of other strategy games both computer based and board based. Currently 'recovering' from a 3 year EQ addiction and trying to get back into turn-based strategy games.
I'd also like to second the idea for a sequel to Colonization, one of my favorites of the 'series.
edit:
LOL, realized I didn't actually answer the question - how did I get started. Like Wildbill (sp?), I played AH war games and looked for a decent computer alternative. Once I found Civ, I basically snatched up anything Sid Meier was involved in.