Thanks, Laura. Nick may wish to speak for himself about his sources. As for me, it's been primarily two: (1) an extremely thorough scouring of the Davenport and Des Moines newspapers of the period, and (2) legal databases containing massive data about Iowa prosecutions of lewdness between circa 1900 and 1975.
As a law professor, I have access to terrific legal databases that have opened up vistas. For the newspaper search, my legal background has helped me, I think, to ask the right questions and to formulate search terms that pull up relevant material.