This is a great topic! I love digging into a car's history - even if I only wind up finding out a few small things, it makes me feel like I've put a piece of the puzzle that makes up that cars' story together.
My Olds was ordered in May of '83 by my grandparents from my cousins' Bronx dealership; it was delivered two weeks later. It was ordered as a base Briar Brown Supreme with a 307, HD suspension, A/C, and a dealer-installed alarm and stereo. I remember the first time I saw it it being so much smaller than the Polara they had been driving around for years. I still remember how awful I thought the new car smell was.
I have an entire folder full of paperwork that's just priceless to me; my favorite being a small notebook that my grandfather kept in the glovebox. He wrote every single maintenance and repair in that book from the time the car was new until the time I wound up with it. Everything from very religious oil changes to the intake manifold that the dealer had to replace when the car was only a few months old.
Not too many people can say they still have a car from their childhood; I have almost 32 years worth of memories tied up in this car. I remember everything from being taken to school with it, to going on a roadtrip to Georgia in it, to my grandfather yelling at me and my brother to stop jumping in and out of the windows ala Dukes of Hazzard, to the first time my grandfather finally (and begrudgingly) let me drive it. Now my son gets to ride around in it, and he loves it as much as I do.