Obituaries in New England can generally be found in the local town or county papers. Many obituaries for Boston and the surrounding area can be found in:
Boston Athenaeum. Index of Obituaries in Boston Newspapers, 1704-1800. Boston, Massachusetts: G. K. Hall and Company, 1968. (FHL book 974.46/B1 V28b; film 823596.)
American Antiquarian Society. Index of Obituaries in Massachusetts Centinel and Columbian Centinel, 1784 to 1840. Boston, Massachusetts: G. K. Hall and Company, 1961. (FHL book 974.4 V42i; fiche 6051402–06.) The obituaries are abstracts of the news items and are listed alphabetically.
Index of Death Notices in the Vineyard Gazette 1850-1875 http://history.vineyard.net/gazdeath.htm
Massachusetts Obituaries http://www.daddezio.com/obituary/depot/OB-MA-NDX.html