I found that a coworker has a large amount of Atari paraphernalia in his office (what a nerd-infested company). When I saw the items, I reflexively rifled through the accompanying software. Then I confiscated everything, took the lot of it back to my office, and systematically researched each gaming title through MobyGames. I generously allowed the coworker to keep any software that was useless to me while I took the rest home for media scanning.
So now I find myself learning the conventions of Atari computers. I know there were a bunch of Atari PCs and this is evidenced on certain games — Atari 400, Atari 800 — and this is if they name a system at all. Fortunately, a little research indicates that these computers are all grouped under the umbrella of “Atari 8-bit”. MobyGames also catalogues them as such, similar to the way the database does not draw distinction between various generations of Windows (95+) or Macintosh games.
The only other thing to figure out before I start earning free cover art contribution points is how to deal with double-sided media that has bits for different platforms on each side. It turns out that this is to be handled the same as Windows/3.x/Macintosh combo media (common with Macromedia Director-based games I have entered). An example of a dual-platform floppy (and tape) is seen in the cover art set for Warriors of Ras Volume II: Kaiv. That disc is already in the database so my coworker was allowed to have that title back.
And I had no idea that Lord British was responsible for anything other than the Ultima series: