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.

Tournament Organisation
General-purpose advice for tournament organizers, specifically in the context of Ultimate Frisbee, but more widely applicable.

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).

Tournament Management
Includes a detailed explanation of the Swiss design.

SportsTournaments.org
Provider of tournament registration and management services for sports in the US and Canada.

LeaguePro Interactive Sports Websites
Provides website and league management services.

SportsNuts
Helps organize and manage sports events, providing online registration, coordination, promotion, and merchandise sales.

Sports Draw
Given a list of competitors does the draw for a knockout competition.

Universal System of Rating a Macrotournament
Mostly in Russian, with one English page on a general theory of rating tournaments.