Many areas have this kind of data, compiled by local pilots for
contests or cross-country flying. In the relatively recent past, I've
seen it for Caesar Creek Soaring in Ohio, the Elmira/Dansville, NY
groups, and the Governor's Cup area in NJ/PA/NY.

Yes, the info can change from season to season and year to year, but
there are numerous landing strips not on the sectional charts that
would be good to have in our moving map databases marked as possible
landing sites. Anyone want to take on responsibility for setting up and
maintaining an open-source, Wiki-type database for soaring pilots in
the U.S.?

Chip Bearden
ASW 24 "JB"