BRHS (Burlington Route Historical Society) member for history of CB&Q and subsidiaries C&S and FW&D. Also covers predecessors like B&MR and QO&KC. Quarterly Zephyr newsletters, annual calendars, & at least one Burlington Bulletin per year. Annual one day Spring Meet in Chicagoland. Annual 2-3 day Fall Meet in different city each year in states served by the BR.
IRM (Illinois Railway Museum) publishes Rail & Wire magazine a couple times a year. Plus unlimited visits to the museum !!!
At train shows, I look through publications from MRHA, CNWHS, RITS, TRRA, & others. When one of these societies’ publications cover a city that was also served by the BR, the articles & maps often include a significant amount of info on that RR’s interactions with the BR.