I don't know of any PURE Halo 2 clans, I know we have HALO clans, in general, from my exp. Halo 2 is pretty much dead, I WISH, and I repeat, I WISH I could still play Halo 2, because I would, but the servers are to laggy and the maps take 40+ minutes to load on some occasions, so its not even worth it.
But thats just me, im sure we have members out there that still play H2, I don't know any personnaly but ill keep and eye out for ya.
Peace
HoSTiLe