Active.com – an excellent repository of information. Check out the “Popular Interests” section for articles not only on Triathlon, but specific to IronMan, Running (including programs for various distances), Trail Running, Cycling, and Swimming.
BeginnerTriathlete.com – a great place to go for learning about the sport, viewing/managing training plans.
Bicycling.com – learn about bikes, gear, repairs, and many other cycling-related subjects.
CoolRunning.com – a good online resource for runners of all abilities and experience levels. Includes current running event information, running-related news, training information, and a number of interactive tools and resources.
CoolRunning.com – Pace Calculator – a sample calculator on the CoolRunning site.
Guide to Triathlon Training – Treadmill Reviews – another web site that lists and links to many good resources to help you learn a little more about triathlons, finding training plans, events, and triathlon organizations.
Slowtwitch.com – Tri Geeks spend countless hours on this site. Their forums are renowned, opinionated, and active.
Triathlete.com – another comprehensive site that includes information on subjects, including training, nutrition, and gear.
TriathleteWomen.com – as the name suggests, articles and coaching recommendations focused on women.
USA Triathlon – USAT home.
USA Triathlon – Training – USAT’s training page, contains some training tools and links to “Training Peaks.”