Greyhound operates the only direct route between Brattleboro, Vermont, and New York City. The bus usually departs Brattleboro in mid-morning, seven days a week. It stops briefly in Springfield before continuing to New York. The bus is air-conditioned and has a bathroom but no other amenities. Tickets can be bought online or ordered over the telephone. Be warned, the Brattleboro bus stop is frequently closed. If you're picking up tickets, it's best to call ahead or get them in advance.
Once you get from Brattleboro to Springfield, your options expand. It's about a one-hour trip, and you can also get there via Amtrak's Vermonter, which leaves Brattleboro once every day. The train trip takes about two hours, and it's a quick taxi from the Springfield train station to the bus stop. From there, you have your choice of as many as 10 buses running daily between Springfield and New York.
Buses between Brattleboro and New York are occasionally sold out, so you might have to travel by way of Boston. Greyhound has one daily scheduled bus between Brattleboro and Boston's South Street Station. It's about a four-hour trip. From there, you can catch one of about two dozen Greyhound buses that travel between Boston and New York every day. Carriers including BoltBus and MegaBus--both with wireless Internet and laptop adapters--also operate frequently between the two cities, leaving every half-hour or hour.