Wikipedia: field recording
phonography.org: a great resource with links to field recordists and lots of info.
phonography yahoogroup: a community of friendly and knowledgeable field recordists, eager to share wisdom on everything from the artistic end to the most infinitesimal technical detail. The vibe is very, very positive; let's keep it that way!
Audio Field Recording Equipment Guide from the Vermont Folklife Center
Binaural (simulated 3D recording)
Green House Music (archive)
Wandering Ear releases are free to download under a Creative Commons License.