Travel:

Logan Airport in Boston is the most convenient. The Barn in Carlisle is about 30 miles north-west and about 40 minutes (when no traffic) from Logan Airport.

Suggested Limo service, if you don't want to rent a car.
About $90 each way.
They will be waiting for you at the gate.
I use them whenever I fly. Arrange several days ahead.
C & L Air Limo
http://www.clairlimo.com
(800) 247–7080 or (978) 692-9303

Lodging:

My recommendation:
Westford Regency, Westford, MA
(This the same hotel where, for years, the February RADIO meets were held. It has a pool, health club, restaurant, and there is a new shopping center and restaurants just down the road.)
http://www.westfordregency.com
Tele: 978-692-8200 – Mention "Antique Radio Auction"
About 4 miles from Auction

Hampton Inn, Westford, MA
(A new Hampton Inn)
http://www.hilton.com/search/hi/us/ma/westford
About 4 miles from Auction

Bedford Motel, Bedford, MA
(An old/basic motel)
http://bedfordmotel.net
About 6 miles from Auction