Stephan Busemann’s Chess Page – This CC GM provides some interesting articles and a section exploring the question of the use of computers in CC.
General
Chess Mail – This is the premier print publication in the world for CC. Lots of online content, including book reviews, player profiles, and downloads of CC games.
CorrespondenceChess.com – “Suite” of sub-sites devoted to CC. Tons of stuff here.
Power Play in the Correspondence Chess Opening
Article 1 – Tim Harding discusses how to play the opening in a correspondence game.
Article 2 – A revisiting of the Power Play, thanks in part (apparently) to Chessopolis.U.S.C.F. Correspondence Page – Rules, ratings, and news from the USCF.
EC Tool – Very popular e-mail correspondence program. Freeware.
Correspondence / Email Chess Software
IceChess – E-mail chess program integrates directly with your mail program.
InterChess – Polished freeware program for e-mail chess. Also includes a chess engine to play against, and homepage keeps a list of potential e-mail opponents.
Mail Chess – Can automatically detect which incoming e-mail belongs to which game, supports Winboard engines for analysis, plus all the usual stuff.
All India Correspondence Chess Federation (AICCF)
Correspondence / Email Chess Organizations
British Correspondence Chess Association (BCCA)
British Federation for Correspondence Chess (BFCC)
Canadian Correspondence Chess Association (CCCA)
Correspondence Chess League Of America (CCLA)
Correspondence Chess League of Australia (CCLA-Australia)
International Correspondence Chess Federation (ICCF)
International E-mail Chess Club (IECC)
International E-mail Chess Group (IECG)
US Chess Federation: CC Section
Atlantic Chess
Web-based Interfaces & Opponent Matching
Chessfriend — Commercial site organizes CC tournaments with cash prizes.
1.b4 Tournaments – Thematic e-mail tournaments at Marek Trokenheim’s b4 page.
Email Chess Tournaments
ChessWorld.net – Offers tournaments, leagues for different skill levels, and team play.