Flight
Bradley is the closest international airport in Connecticut. Providence, RI is also a nearby option. You might be able to find a cheaper ticket through LaGuardia if you don't mind driving from NYC!
Hotel
We recommend looking at either the Hilton Garden Inn Groton or the Mystic Marriott Hotel & Spa. There are also plenty of other hotel choices in the area if you're planning to stay in either Mystic or Groton for the wedding.