ShovelScout

ShovelScout finds the public posts where people are already asking for something like what you sell. You type a phrase, say "invoice automation", and it goes through Reddit, Hacker News and a few business forums looking for the sentences where someone asks for a product, a recommendation, or an alternative to what they use now. Each result links back to the original thread, so you can read the conversation and answer there yourself instead of sending a cold message. It is free to search and needs no account. Only public posts are readable, so private groups and paid communities are out of reach.