Rayman:What did we all do before the internet when we wanted to learn about something? We went to the library (or at least I did). There are a bunch of NRHP Contributing Buildings near me that I want to waymark, but can't find squat about them. I know the central library in Buffalo has an extensive local history section, so I intend so go there some snowy weekend afternoon and do some research.
Historical societies are good for this, also. I have been fairly fortunate in finding material on line for many of the historic districts I want to waymark contributing buildings in, but if I ever start running out of things to waymark (say in about 40 years), I figure I may start trying to scrounge hardcopy material for libraries and historical societies.
When I was planning a stop in Cumberland Gap, I e-mailed some folks at a historical society to get electronic copies documents about the historic districts in that area. They were very accommodating.
My eldest son lives about an hour from Savannah and I have made a couple of waymarking/geocaching trips there. Its an AWESOME city with the largest historic district in the country (as far as I know). I ended up buying a book about the historic districts in the city that detail all the contributing buildings. There are over 100 historical markers in the county, a third to a half of which had been waymarked before I went there. I've been to about 3/4 of them now, visiting the ones that are already waymarked and waymarking the others.