There is bus service with connections to Montreal and Burlington to the north and Rutland, Bennington, Boston and New York City to the south. See the Greyhound and Vermont Transit websites for schedules.
Middlebury is compact, but it's worth having a car to see the nearby countryside.
Middlebury College has a picturesque campus just outside of the town center. There is a waterfall and bridge in the Frog Hollow area downtown with numerous restaurants and galleries.
The Middlebury Inn is a good upscale choice. There are numerous B & B's and motels nearby to fit all budgets. Check the Middlebury College schedule before visiting, as area hotels are completely booked for graduation and other major events. Book well ahead if coming during leaf season (late September - early November).