I'll be honest, I don't have a ton of experience when it comes to finding investors, and other early stage enablers. However, when it comes to your market, I think the question is better asked, who is your audience?

Who do you expect to use this product day in and day out? And then make it even smaller and go look for those people on LinkedIn, Reddit, HackerNews, Twitter, etc.

Then just hit them up. You don't have to be selling necessarily, you can simply be asking about the problems they might have or looking for feedback on something.

Obviously this depends a lot on B2C or B2B, but there exists a community of people somewhere with the problem you're trying to solve or a company which is kind of a community :D.

If you can't find an audience, then I think that also answers your question.