I've found it impossible to get good maps of interurban systems especially in relation to the steam roads, but I notice that the revised volume of the "Railroad Atlas of North America" covering IN, MI and OH has got all the interurban lines as well as all historic lines and stations. They are promising to do this with all future revisions, but I think they are following Hilton and Due's book on the subject and are not doing trolley lines.
See www.spv.co.uk
See www.spv.co.uk
