AeroPac's: "Association of Experimental Rocketry of the Pacific" organizes regular high power rocket launches in Northern California and Nevada.
Amateur and Ex Rocketry: Information on motor construction, tooling and supplies.
Amateur Experimental Rocketry: Rocketry.Org maintains a large web database of suppliers for anything experimental rocketry enthusiasts could want, as well as a global rocketry organizations database and book lists.
aRocket: Resources for amateur and experimental rocketeers.
Ben's Chemical Propulsion: Tutorials on amateur experimental rocketry, along with videos, launch reports, and pictures.
Blacksky: Real rocket science. With references and design equations.
Commonwealth Displays: Rocketry site for project parts you need.
CTRA-NARCONN: Connecticut Tripoli and National Association of Rocketry. Lists launch information, recent launch photos, contact information or member application.
Designing Rocket Motors: Publications, articles, software and discussion groups about chemical rocket motors.
Digital Wireless Firing Systems: Digital electronic firing systems for the model rocket enthusiast.
High Power Rocketry: This site answers the question: What is high power rocketry?
International Experimental Aerospace Society: A knowledge base containing information on experimental rocketry, regulations of various countries, and information on grant opportunities.
Jetex Engineering Works: Reference resources about Jetex and Jet-X micro rocket motors and propellants, plus gas generator experiments and propellant development projects
Model Rocket Drag Analysis: NAR R and D Report
National Association of Rocketry: The NAR is the oldest and largest sport rocketry organization in the world.
Pacific Rocket Society: An experimental rocket society, dedicated to liquid propulsion research.
Project Earth Crashlander: The Chronicles of Experimental Rocketry. Contains several personal rocketry projects that go into detailed explanation that anyone starting in scratch-built rocketry might be interested in.
Richard Nakka's Experimental Rocketry: General information on what amateur experimental rocketry involves, and considerable specific information on motor and rocket design.
RRS: The Reaction Research Society is the oldest continuously operating amateur experimental rocket group in the United States.
Swiss Propulsion Laboratory: SPL develops propulsion elements for sounding rockets like LOX valves, injectors, regeneratively cooled combustions chambers, igniters, propellant feeding systems and thrust test stands.
Systeme Solaire: Information on how to build the SS67B-1 liquid propellant rocket engine.
Trailer Trash Aerospace: A group of high-power and experimental rocket enthusiasts in the desert southwest building magnificent things with the thinnest of resources.
Tripoli: Tripoli is a non-profit organization dedicated to the advancement and operation of non-professional high power rocketry. Tripoli has members in the United States and 20 countries around the world.