I thought about it, and even have a ~/code/iso-3166-2 directory with some stuff in it, but the problem is that I'm not entire sure how accurate/complete this data is either. It's certainly enough for my use case as it's specifically tied to GeoIP, but it's not inconceivable that there are missing entries (or outdated/wrong ones, for that matter). Perhaps there are regions which don't have an IP address in the GeoIP database (like some of the small pacific island states)? I don't know...
ISO does have a browsable website[1] and you can get the data from there, which is the best "official" source I know of, but it's not easy to extract the list from there. It's probably better to shell out the €80 (less than the €200 I remembered) to just buy the damn PDF than spend a day writing a script to extract the data from there, but I'm kinda poor at the moment, so... :-/ Also no idea if that buys me updates as well (being outdated is a big problem with many of the lists I found, turns out countries change, who knew).
Wikipedia also has pages for them[2], but again, I'm not sure how accurate/complete/updated this is.
