See also:

Games: Video Games: Multiplayer: Leagues -  (26)

Games: Video Games: Shooter: Clans and Guilds -  (115)

Case's Ladder - - Parent site for multiple competitions, includes links to leagues in specific games.

ClanBase - - Includes results and contact information for competing clans.

Elite Clan Warfare - - Playing spearhead, Call of Duty:United Offensive, and Counter-Strike:Source. Includes player/team statistics and downloads area.

Online Gaming League - - Includes forums, supported games list, and rules.

ProLeague - - Counter-Strike series leagues organised by country. Prizes available.

QuakeCon - - Annual event with multiple games. Forum and gallery of previous years.

Squad Games - - Includes forums, downloads, results and fixtures.

United Gaming Clans - - Playing TFC and Counter-strike. Includes news, fixtures, results, forums, downloads and IRC chat.

WarLeagues - - Includes gallery, downloads, forum and competitor information.