Word-of-mouth leads in Pittsburgh after 3 years as a janitorial supervisor

A friend who works at a local manufacturer says there are openings not advertised online. It has been a long 17 weeks. 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.