To find local banks, simply do a Google Map Search with the query
“Bank near Cambridge, MA, United States”
Additionally, you can also click on “Similar Pages” for more banks.
You will then have a good overview of what is available locally.
Bank of America
Formerly Fleet Boston, now Bank of America, has over 4000 ATMs in 13 states and is suitable for Boston, Cambridge, NYC and most of the East Coast states (incl Connecticut, Delaware, Florida, Maine, Maryland, Massachusetts, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, Vermont).
Most banks have an ATM locator on their homepage also informing about the shortest distance to cash and fees.
US checks can be handed in at various German banks for varying fees. It is worth checking the differences if you intend to use checks routinely. Volksbank was charging only EUR 12.50, independently of amount on check. Other banks take $13 for international transfers.