I believe that most NYC bike shops should stock the TransAlt bike maps (ie. the Westchester county and CT maps) but I don't live in NYC and can't verify for you.

You can request a copy of the Rhode Island bike map from the the state's DOT website

You can buy bike maps from Massachusetts from the Rubel bike maps website

oh, and also, not to get all lazyweb on you, but all of this stuff came up as first (or almost first) hits on

Google: {new york bike map}
Google: {connecticut bike map}
Google: {rhode island bike map}
Google: {massachusetts bike map}

just sayin'.