What I'd do after getting the data on what programs simply exist is to set up a form where people can submit reports that such-and-such program serves this-or-that need (and therefore needs this-or-that tag). Some manual validation or cleanup will probably be necessary but it's crucial to get as many reports on as many programs as possible: any individual report can be incomplete or even incorrect, but the more you have the more you reliably know about any given program. Then it's a matter of generating publicity: blog, post on social media, explore partnering with disability support and activist organizations or getting sponsorships.
The Wine AppDb is an example of a website that does something similar to build a community-driven database.
This sounds like something that needs to exist. Good luck!
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