Looked at several plugins through WordPress.org, and tried a couple. Google Maps Widget was so easy to set up.
However, couldn't get it to work - turned out there was a conflict with Portfolio Slideshow Pro. The Webfactory looked at it and diagnosed two instances of Fancybox. Turned this off in Portfolio Slideshow Pro (which is also a great plugin), and now everything works just fine.
So, good plugin, quick support response.