I have a similar problem with a free service I am releasing in the coming weeks. I just asked a guy that writes a newsletter about startups. He suggested I g

I have a similar problem with a free service I am releasing in the coming weeks. I just asked a guy that writes a newsletter about startups. He suggested I go where the users are of that niche. Maybe you could try Betalist ? Finding people in that niche on twitter would also help. Connect with them then send a few PMs as ask for their feedback.