|Historical Society of Windham, ME|
c. 1833 school house
|Glastonbury, CT Historical Society Building|
Welles Shipman Ward House, c. 1755
Other information that I have accessed online, and have by visiting local historical societies during my research are their publications. You may have seen some of these books on town histories that have been published in recent years. Sometimes special books will be printed for centennial celebrations. My favorites are town history books that were written hundreds of years ago, available at Google Books or Internet Archive. I have found many items that have prompted scenes and even stories. Census and marriage records are also a great way to get authentic character names that were used in the locale. These, too, are kept and sometimes published online by historical societies.
Historical societies are categorized by town, county, region, and state. Most towns have a society, many have have buildings where information is archived, many have small museums, and often they a web presence. State government websites usually provide a list and town websites will often have a link.
A word of caution. Each society has their own guidelines for queries. Some are free, sometimes they charge. Societies are usually operated by volunteers, some with much knowlege and some are there just holding down the fort. So be as specific as possible and ask to speak with the historian who has research knowledge in that category.
Also, keep an eye on historical society events calendars. I've attending several events through the years that have been educational and given me much inspiration for writing.
Remember, the mission of historical societies is to preserve and record the past ~ an excellent resource to access when authenticating your novel.