Michael Plummer, owner of Tampa, Fla.–based marketing firm Our Town America, advises clients on how to market their stores ­effectively to new residents in town—and why “mover” marketing works.1. Seventeen to 20 percent of the population moves every year and those people are looking for a whole new set of things: a new grocer, a new auto mechanic.… They’re in that searching mode.2. Mail a discount card or gift certificate to new residents—in an envelope that will catch their attention.3. Where to find contact info? The data is out there; it’s been out there for years. Utility