Tournament Designs  
   12 teams wish to play an all-play-all at 6 venues over 11 rounds. Schedules for such all-play-all tournaments up to 26 players, and for carry-over tournaments up to 16+16=32 players, in HTML, PDF and txt formats.
   http://www.jdawiseman.com/papers/tournaments/tournaments.html

Tournament Organisation  
   General-purpose advice for tournament organizers, specifically in the context of Ultimate Frisbee, but more widely applicable.
   http://www.afda.com/promotion/tournament_organisation.htm

Tournament Organizing  
   Advice for orgainzers of Go tournaments, with particular emphasis on the judicial aspects (which would apply equally to a tournament of any similar game).
   http://www.kttl.helsinki.fi/msiivola/rr_commission/tournament.html

Tournament Management  
   Includes a detailed explanation of the Swiss design.
   http://www.oxfordcroquet.com/manage/index.asp

SportsTournaments.org  
   Provider of tournament registration and management services for sports in the US and Canada.
   http://www.sportstournaments.org/

LeaguePro Interactive Sports Websites  
   Provides website and league management services.
   http://www.leaguepro.com/

SportsNuts  
   Helps organize and manage sports events, providing online registration, coordination, promotion, and merchandise sales.
   http://www.sportsnuts.com/

Sports Draw  
   Given a list of competitors does the draw for a knockout competition.
   http://www.sportsdraw.co.uk/

Universal System of Rating a Macrotournament  
   Mostly in Russian, with one English page on a general theory of rating tournaments.
   http://www.rt.ustu.ru/