carbonel

The last I checked, the Amtrak software had trouble with anything more complicated than a simple round trip that involved going to Canada; you might have to put this one together yourself. If it's any help, there's exactly one train a day from New York (or Albany, or anywhere along there) to Montreal, and one back: the Adirondack.

You might also do better getting information or reservations by phone, once you get past the automated voice. ("Julie" is fine if you're standing in a bus station and need a last-minute train reservation, or want to know whether a train is on time, but this is probably beyond that software as well.)