This a couple of days old, but in case you missed the news of the unearthing and restoration of a cache of important recordings, see this New York Times article about the National Jazz Museum. Then read this followup. It will probably be a long time before the trove of new old music by Lester Young, Count Basie, Benny Goodman and others can make its way to the public in commercial albums.
In the meantime, the museum offers a few tantalizing samples.