If it's remotely technical looking for for an Awesome-whatever page on github is always a good start. From there, I usually look for relevant subreddits and see

If it's remotely technical looking for for an Awesome-whatever page on github is always a good start. From there, I usually look for relevant subreddits and see if they have active wikis. Generally you just need to find an 'in' to where the community in question is most active (or was before it died) and links will snowball until you've covered most of what's available. Either way there's often a lot of 'I am now on page 104 of 321' on a github search, itch.io list, etc. so there's still a large amount of manual labor. There's also a bit that comes just from having varied experiences and thinking about how things are related, for example, the aforementioned ORCA has an entry [1] on Esolangs.org, so knowing that I can also add the term esolang to my keywords for searches and mix-and-match relevant keywords until I've covered most things. Of course, the best resource is someone that's already passionate about whatever you're looking for. I run a chat on Telegram mostly about Modular Music [2] (VCV Rack, Eurorack, etc) but we talk about tools like ORCA, Pure Data, FoxDot, SonicPi, etc. and that's led to finding a lot of links too. [1] https://esolangs.org/wiki/Orca https://esolangs.org/wiki/Orca [2] https://t.me/vcvrackchat https://t.me/vcvrackchat