Jobs at small San Diego companies nobody posts about

A friend who works at a local manufacturer says there are openings not advertised online. I would rather hear the honest version than the polite one. 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.