American Amateur Baseball Congress
   Coordinates play among US leagues in seven age brackets, from sub-teens through adults. Includes rules, tournament dates, and list of regions and age divisions.
   http://www.aabc.us/

American Amateur Baseball Congress of Oklahoma
   Features information on the organization including bylaws, links, officers, as well as state, regional, and world series tournament information.
   http://aabcoklahoma.com/

National Adult Baseball Association
   NABA amateur baseball organization information, including tournament results, events and how to join.
   http://www.dugout.org/

Over 50 Baseball
   Promoting an affordable week-long fantasy-camp type fun tournament in Las Vegas each October. Also promoting the establishment of local leagues nationwide.
   http://www.over50baseball.com/

Roy Hobbs Adult Baseball
   Amateur baseball organization for adults over the age of 28.
   http://royhobbs.com/

Team One Baseball
   Scouts baseball's high school, college and minor league players and compiles information on the annual Baseball Draft.
   http://teamonebaseball.rivals.com/

Ventura National Adult Baseball Association
   League guide to teams for people age 18 and older. Features information on team play, current standings, newsletter, and game schedules for amateur organization.
   http://www.venturanaba.all-city.com/

Vintage Base Ball Association
   Listing of rules, tournaments, members and contact information.
   http://www.vbba.org