I'm a firm believer that when doing genealogy research no stone should be left unturned. You never know where you will find that one missing piece of information that connects a family puzzle. Here is one place that may not appear to be of value at first, but dig deeper and you may find something through the the resources they link to at the Railroad History Archive at the Thomas J. Dodd Research Center at the University of Connecticut.
The archive is comprised mostly of "individual collections of administrative records, photographs, maps, timetables, ephemera and many other types of archival materials. The collections focus almost exclusively on the history of the railroads of southern New England, particularly the New York, New Haven & Hartford Railroad." Be sure you also check out the "collections list" for additional records. I must tell you that the University does make it known that "personnel records and worker files were not included in the donation of the corporate records and there is virtually no personal information about the company's workers" in this archive. However, make sure you click on "Links to Railroad History Resources in the United States." You will find many links to other railroad resources where you may find something. Some of the links are free resources and some are fee based, such as the U.S. Railroad Retirement Board. They have a fee similar to the NARA for the research.