Why would you want to do this? Let's say you need to plot a route to tour college campuses, or maybe you want to find the closest place for all your friends to meet for dinner. If you have the addresses in a spreadsheet, you're halfway there.
You do need to register for an account with Brian Sobel's website, mapalist.com. It will use your existing Google Account to find the list of addresses you want to convert into a map. If you don't have a Google Account, it will prompt you to create one. You can choose whether maps you create are private or shared.