The first D&D product I ever bought was the original white box. Unfortunately, I only have part of the original contents. When I left Germany, I foolishly mailed a big box of stuff home including all the Dungeons and Dragons stuff. Customs inspected the box and did not seal it back up properly. The box split open in the mail. I lost half of my books, all my copies of the Strategic Review, and most of my copies of the Dragon. I insured the package, but the Post Office would only pay for the things I could document. I got about $20.
I always preferred to create my own campaign rather than buy modules. The one exception was Tegal Manor. I still have my original copy of Tegal Manor. That was an awesome adventure from the Judges Guild.