Scooter
Scooter Seat Covers- handmade and wild

Apparel, Accessories
Hot Biker Stuff - Leather Biker Apparel and Accesories

Airbrush, Custom Paint
Rocket Workshop - Sportbike customizing, near SF
Motofetish - Beautiful helmet paint, in SF
Jay's Grafx - Big gallery of custom work, in IL
Xtreme Creations - Cool motorcycle, helmet graphics, in NJ
Uptown Grafx - Urban designs, club logos, in ATL

Motorcycle Training
Motorvike - Street and Dirt classes in LA, Ventura counties

Forums
Bay Area Riders Forum - Moto forum for SF Bay area
Wootbike - Informational articles on motorbiking

Touring, Adventure
Pashnit - Excellent road guide for California
Trek Now - GPS routes in US for back and offroad

Racing
AFM - American Federation of Motorcyclists
Snarl Sport Racing - AFM racing team, two-strokes, carts