The official site of the Road Runners Club of America, this is the best source for finding a running group in your town. You may, however, still have to do a little legwork to find out which group will best suit your ability level. U.S. Masters Swimming offers coached workouts at pools around the country for swimmers of all levels, aged 19 and up. Their website will put you in contact with a local group and keep you updated on swim meet information. It has over 500 clubs across the United States, each of which is responsible for organizing local walking events and mapping out walking routes.
Members often walk together on weekends and during the week.
As they accumulate hours, they receive incentive prizes given by local merchants. Many members meet and walk the malls together. This site chronicles competitions in just about every sport imaginable, from running to in-line skating to, yes, even horseshoes. It's also an excellent resource for workout clubs, both online and in the real world. Calif. Her articles have appeared in Health and Cosmopolitan magazines and many other publications.