The national model airplane organization in the USA is the Academy of Model Aeronautics. The AMA formalizes the rules for the American speed events and also sanction contests. The competition rule book is on the site.
THE message board dedicated to C/L Speed.
This site has news on C/L from all over the world.
A site also covering speed with an emphasis on Jets.
Site dedicated to FAI Control Line Speed class – F2A.
This site has several interesting articles on two-cycle engines. Look under the “old tech info” link.
A wonderful site from Australia devoted to props. Has articles on balance, prop failures, airfoils, and more.
Bolly, the propeller people, have a technical site.