Word-of-mouth leads in Detroit - 14 months and counting

Two small Detroit employers told me they are hiring but have not posted yet. There are 4 people counting on me, so I am trying to be careful. One is a print shop, one is an accounting firm and one is a clinic. What do you write in a cold email?

Thanks for writing this out. I went through something close to it 14 months ago, and it settled down once I kept a simple log of every call and form.