Word-of-mouth leads in Raleigh after 3 years as a recruiter

A friend who works at a local manufacturer says there are openings not advertised online. It has been weighing on me all week. They like a brief email with a résumé. Should I visit in person?

Visiting in person worked for a trades job. For office jobs, email was better.

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