Reference Point System

An optical system developed in Norway which makes judging offside easier. Diagrams, reports, testing, and contact details.
http://www.rps.as/

J.A.S.O.A. Soccer Referee site

The overseas branch of the US Soccer federation referees in Yokosuka Japan.
http://jasoa_soccer.tripod.com/

The Last Word

This site is visited by referees from around the world. The forum is especially popular, with discussions on a variety of topics going on all the time.
http://www.ibiblio.org/byers/ref/

Dansk Dommerfomidlign REFEX

An organisation for the international exchange of referees for youth tournaments.
http://www.refex.dk/uk/index.html

The Motram Refereeing Assistant

A modern technology system to offer referees instant, accurate information on the position of the ball during a game.
http://www.motram.com/