Jobs at small Boise companies nobody posts about

Two small Boise employers told me they are hiring but have not posted yet. I am in Boise, in case local advice matters. One is a print shop, one is an accounting firm and one is a clinic. Should I visit in person?

A short email with two sentences about what you can do and your résumé attached worked for me. I followed up after a week.

Small employers often hire on recommendation. Ask neighbours, former co-workers and your library.