For me, the "computer geek" bug bit pretty early. When I was 12 or so (early 80s), I had a friend whose father bought him a TRS-80 Color Computer. He'd have sleepovers at his house and we'd stay up very late hacking out "games" (loosely defined) that were of the Choose Your Own Adventure variety. They were completely text-based and offered multiple choices at each turn. We learned quickly to map out the story's flow on graph paper.
It didn't take long to decide that I needed a computer of my own, so I started saving. Eventually, I got a paper route for the San Jose Mercury News and that helped me reach the savings goal pretty fast... I was pretty excited to purchase a Commodore 64 with my own money. My parents helped out by buying me the cassette tape drive (so I could [painfully and slowly] save my work) and a dot matrix printer. The following Christmas, my grandparents bought me the 300 baud modem for it (funny story: I learned years later that my grandparents argued over whether to get this because they'd just seen the film War Games). A year or so later, I bought the disk drive for it... which was both more expensive and physically larger than the computer itself!
I spent a whole lot of time hacking on that thing, including punching in program after program from "Compute Magazine". You'd punch things in by hand and try to run it later... but it was guaranteed not to run, so you'd have to go back through and try to find the typo.
In high school, I got in trouble once in a History class and was given some "extra" homework -- I had to write "I will not cause a disruption in Mr. Whatever's class in the future" a hundred times. I asked the teacher if it would be alright if I typed it a hundred times because A) I had a lot of homework and B) I needed the practice typing. Not having any idea what he was agreeing to, he said it was alright.
I went home and wrote something like this:
10 FOR I = 1 TO 100
20 PRINT "I will not cause a disruption in Mr. Whatever's class in the future."
30 NEXT I
Fire up the printer, run it, and I was done... I remember this because it was the first time I realized that I could make a computer work hard so I wouldn't have to. Thus, a career was born.
That computer was also my first experience with the online world. I had to borrow my parents credit card to make it happen, but I got my first Compuserve account with that C64. Between cruising forums and writing code to peek/poke sprites on screen, I spent hundreds of hours on that machines.
Later (shortly after high school), I got an IBM PC XT 8088 clone that had two 5.25" floppy drives in it. One was the system (the OS and whatever app you ran) and the other was for data (to save your documents or whatever). Later, my uncle hooked me up with a 10MB hard drive... it was a beast and sounded like a jet taking off. I still remember messing around with jumpers to get it all working.
That 8088, with an amberchrome monitor, was the computer with which I first combined my other hobby -- music. I bought a serial port MIDI adapter and the original release of Cakewalk for DOS. Connecting a synthesizer to a computer opened up an amazing new world to me. I've been a Cakewalk (now SONAR) user ever since, despite dabbling with other products. It just "feels right" to me.
From there, it's been a series of 286, 386, and so on... I've never owned an Apple computer (though the MacBook Pro is sure tempting these days) and have been a PC junkie for over 20 years now.