House of Blues
15 Lansdowne St
Great concert venue! Inexpensive tickets, easy access, and always a great view. I've never been disappointed. I've only seen country acts here but I know they have a long list of events.
100 Legends Way
Saw the Avett Brothers here. Fun venue, good beer selection, great performers come through. Reasonable prices for the most part, considering where you are. Easy commute on rail back to suburbs.
Boston > Live Music > Country & Folk