Find a library that is listed as a repository site. The Detroit Public Library is one such library. My experience has been excellent. I found a 1944 topo map of the See-Selune Plain where the 30th ID made its stand at Mortain. I'm currently making a scale PL map to recreate the battle and potentially study for CGSC (now ILE - intermediate level education).
Carl,
I've enjoyed playing PL/PB since the early 80's. I have not developed any variant products to date but as an Army Reserve officer am interested in history. I have read extensively about warfare on the Eastern Front in order to reap the benefits of that forgotten portion of WW2.
As I stated, I am developing a 4 hex to kilometer map for the Battle of Mortain. In so doing, I researched topo maps and found that repository libraries are required to maintain maps, including historical maps. I found a map of the Avranches - Mortain - St. Hilaire - Ger area circa 1944...great find.
Though not 100% realistic, PL/PB have been useful in instructing the concepts of combined arms which leads naturally to the current era of jointness in the US military; kind of AirLand Battle to Shock-And-Awe
