Last updated 7/2/2002.
Boston U.'s Van Helsing Society and their Masquerade LARP (with a new chronicle every September).
Dreams Dark and Bright. This LARP, put together by Ken Peterson and Sami Genstein (aka Ender and Trill from the Chi Mu motley in the 1998 game) was never, so far as I know, actually run, but it has a fairly detailed "non-canonical" setting for Changeling in New England and is a good place to start with Changeling character creation, at least until you buy yourself the official rules in The Shining Host and The Shining Host Players Guide.
Forthcoming Camarilla-affiliated Changeling and Arcanum games in southern New Hampshire, to be run by some o' me mates from the Midsummer game and/or Van Helsing. (Currently the link is for the Yahoo Group.)
Winter's Edge is a long-running Shining Host LARP in Philadelphia.
Innocents Lost is an organization of interconnected MET LARPs, including Changeling games.
Hub of the Universe, a Changeling setting for Boston (but not the one I used for my LARPs).
Witch City, a Changeling setting for Salem, MA (where I happen to reside, though I don't know these folks).
A Changeling Storytellers' resource page, The Right to Dream.
Changeling stories, art, a discussion forum, and more can be found at the Moonlit Trod.
Endless Dreams, a new site offering still more Changeling goodness.
A fairly exhaustive and useful collection of Changeling tabletop errata and clarifications can be found on the "Scattered Dreams" site.
Changeling news and release information compiled by Mistypaw.
C.J. Cherryh's Latin primer. I include this as a game link in order to support Proper Latin in role-playing games, not that it matters to the world at large, but jeez, how hard is it when writing, oh, say, a book about the Sabbat to realize that "ductus" is better translated "drawing" or "duct" than "pack leader"? Buy a fucking dictionary. And then use this beginner-friendly page to get the case endings right.
Lots of White Wolf game geek links at BJ Zanzibar's WoD.
Check out the game company itself: