I've been collecting emails for 9 months, primarily by spending $3k on Facebook ads to send traffic to blog posts. 1,500 emails so far.

My acquisition process right now is a "call me to sign up" after showing prospects a demo video. Not ideal. I'm working on making the app (filled with a model farm's data) live for users to test for a couple days (gated behind an email opt-in) and then allow them to sign up online. We'll see!