I am a believer in folk radio. Here are the archives for FolkDJ-L, which includes individual Folk DJs' playlists as well as monthly and annual compilations of airplay lists. Favorite radio stations include WTMD (Towson MD), WOBC (Oberlin OH), WUMB (Boston), WPXN (Philadelphia), and WFUV (New York).
House concerts are one of the best and most intimate ways to see high-quality folk music in the Baltimore-DC area. Favorites include Panzer House Concerts, Moore Music (in the House), Folk 'N Great Music, and Cooper's House.
Favorite local(ish) venues include Focus Music (Rockville MD and Alexandria VA), Uptown Concerts (Baltimore MD and Sykesville MD), Jammin' Java (Vienna VA), The Birchmere (Alexandria VA), and World Cafe Live (Philadelphia).
Festivals are a great way to be exposed to a lot of new music in a concentrated weekend. In terms of line-up, after-hours music, and community, Falcon Ridge Folk Festival (Hillsdale NY) is one my favorite of the larger festivals.