UltraRunning Magazine  
   Magazine for ultramarathoners, with calendars, race results and reports, techniques and tips.
   http://www.ultrarunning.com/

Stan Jensen's Ultramarathon Guide  
   Provides general information on the sport, especially focusing on northern California. Includes information and statistics for the top races in the USA, as well as personal achievements, and goals.
   http://www.run100s.com

Marathon and Beyond  
   Published six times a year - website contains tables of content, sneak previews and ordering information.
   http://www.marathonandbeyond.com/

Hal Higdon: On The Run - Ultramarathon Training  
   While focusing on the Comrades Marathon, author Higdon provides a training plan useful for a wide range of ultras.
   http://www.halhigdon.com/ultramarathon/ultramarathon2000.htm

North Texas Trail Runners  
   Information on trail running and ultra running in North Texas. Features calendar listings and a news/opinion section.
   http://www.nttr.org/

Running the Hardrock 100  
   First-hand account of running the Hardrock 100 through Colorado's San Juan Mountains by Bob Boeder.
   http://www.oldmp.com/hardrock100/

American Ultrarunning Association  
   Membership details, race listing, USA National Ultra Team, description of the organization and related links.
   http://www.americanultra.org/

UltraRunner.net  
   Resource for clubs and races in North America with upcoming events, pictures, related links, mailing list and course descriptions.
   http://www.ultrarunner.net/

Ultrafit Endurance Sports  
   Company that specializes in products designed for the endurance athlete.
   http://www.ultrafit-endurance.com/

Pacific Association Ultrarunning  
   Official USATF ultrarunning site for northern California and Nevada. Includes Ultra Grand Prix standings, race calendar, and results.
   http://www.pausatf.org/data/Ultra.html

New York Ultra Running  
   Contains details about races in the area, highlights, pictures, directions, and membership details.
   http://www.newyorkultrarunning.org/

Extreme Ultrarunning  
   Resources, links, and general information. Includes runners' profiles, calendar, photographs and race reports.
   http://www.extremeultrarunning.com/

Australian Ultra Runners' Association  
   Seeks to promote ultramarathon running in Australia. Provides a race calendar, results, news, and links.
   http://www.coolrunning.com.au/ultra/

International Association of Ultra Runners  
   Provides organizational information, newsletters, race listing and coming events, training tips, and links. English and Chinese versions.
   http://www.iau.org.tw/

Ultramarathon World  
   News service for runners who compete at distances beyond the standard marathon of 42 kilometres, 195 metres. Source of information on ultramarathon races, runners and activities.
   http://www.ultramarathonworld.com/

Sri Chinmoy Marathon Team International  
   Sponsor of multi-day races, including the world's longest certified race of 3,100 miles, triathlons, and many ultra events in more than 30 nations. Includes news, photos, race information, library and links.
   http://srichinmoyraces.org/

Kansas Ultrarunners' Society  
   Includes event descriptions, member biographies, pictures, newsletters and membership information.
   http://www.ultrarunners.info/

St. Louis Ultrarunners Group  
   Provides club news and events, including registration materials.
   http://www.stlouisultrarunnersgroup.net/

UltraOz  
   Includes news, links, and race descriptions.
   http://www.ultraoz.50megs.com/

Ultrarunners Organization  
   Includes descriptions and links to events, photos and contact information.
   http://www.ultrarunner.org/

Sri Chinmoy Marathon Team New York  
   Multi-day events, including an annual 3,100-mile race. Information on upcoming races and events, articles, and contact information.
   http://www.scmtny.org/

The 100km Association  
   Club serving Britain. Includes news and events, club information, message board, and race results and reports.
   http://www.carey.abelgratis.co.uk/100km/index1.htm

Marathon of Britain  
   News, the team, photographs, faq's, and community.
   http://www.marathonofbritain.com/

Cascade Running Club  
   Hosts 100 mile, 50 Mile and 50K minimalist runs in Washington. Includes club information and race details.
   http://www.cascaderunningclub.com/

Kevin Sayers UltRunR Site  
   Resources and opinions on topics ranging from training and racing tips to equipment recommendations.
   http://www.ultrunr.com/

AC100 RaceBook  
   The official record and program of the Angeles Crest 100 Mile Endurance Run. Includes course and driving maps for runner and crew. 1986-2001 information.
   http://www.geocities.com/ac100racebook/index.html

Will Brown's Umstead 100 Report - 2001  
   Will Brown conquers the 100 mile distance at the 2001 Umstead 100 Mile Run in Umstead State Park, Raleigh, North Carolina, April 7-8, 2001.
   http://www.geocities.com/madeads/will01-100.html

Ultra Adventures  
   Comprehensive regional ultrarunning resource focusing on North Carolina and the Mid-Atlantic region.
   http://www.ncultra.org

Endurance Sport Club  
   International organization, based in Canada, that sponsors a number of fat-ass style ultra-races. Includes membership information and race calendar.
   http://www.ClubFatAss.com

Team CRUD (Coloradans Running Ultra Distances)  
   Ultra trail running information, photographs, news, and links.
   http://www.teamcrud.com/