Kick!

A comprehensive guide for runners, with 2000+ race listings and hundreds of pages of knowledgeable advice on all aspects of running, training, and injury prevention and recovery.
http://www.kicksports.com/

Runner's World Online

Online version of the print magazine.
http://www.runnersworld.com/

Advantage Athletics

Training methods for sprints, hurdles, pole vault, jumps, throws, and weight lifting.
http://www.advantageathletics.com

Elite Track

Training articles for all events, plus links, message boards, and a chat room.
http://www.elitetrack.com/main.php

ISBS Field Athletics - Coaches Information Service

Research results in sport science with implications for coaches and athletes.
http://www.education.ed.ac.uk/research/projects/theme8/index.html