Motorcycles
Moped Riders Association - http://www.mopedriders.org/
Resource for the International Association for the Advancement of Moped Riders. Has links to dealers and a forum.
Replika Maschinen, Inc. - http://www.replikamaschinen.com/
Motorcycling tuning service that offers a two and four stroke cylinder head porting and air flow facility. Based in Santa Clara, CA.
Sport-Touring.Net - http://www.sport-touring.net/
Sportbike dedicated website. Site has links to other resources as well as a discussion forum.