The Bikery: Local bicycle store with many parts. Easy to work with, highly knowledgeable staff. Brakes, Tires and custom wheels.
Blue Sky Design: Sell a great kit car, the aerocoupe. many new teams have cut their teeth on this car, and many are still cometitive!
American Power Sports: Great place for sprockets, chains, and other drive components and supplies.
RJS Racing Equipment: Custom five point safety harnesses in a wide variety of sizes and styles. See this for measuring the belt before buying!
KTA EV Services: Great Electronics & Motors, but no longer sell to NEW electrathon customers. Previous customers only. Great stuff for EV conversions though if you are ready for the next step.