Ask HN: How should I do customer development for a SaaS product?

If I want to make a SaaS product for SME's, where do I find online their owners and talk to them about their pains and how my product could solve them? Is it LinkedIn?

To be honest, I don't have a clue about how should I approach customer development for a SaaS product that is targeted to SME's.

Any help is highly appreciated!

Thanks!