Boatbrochure.com Extensive collection of brochures and plans (enter 'Columbia 50' in the search box).
Columbia 50 Insurance-Grundy Insurance Special deal from Columbia 50 Owner Jim Grundy who also is the President of Grundy Insurance Co. "One thing that might be beneficial to C50 owners is our Classic boat insurance program. As I’m sure you know underwriters are resistant to older boats. We insure them and obviously Columbia 50’s get preferential treatment..."
Columbia 50 "Knuddel" website A great website dedicated to the C-50 Knuddel (Knoodle), presently located in Porto Rotondo in northern Sardinia (Italy).
Columbia 50 & Spinnaker Socks "Lady Lou" demonstrates use of a spinnaker sock in a photo sequence taken in the 2011 Classics Race in Rio de Janeiro.
Columbia Yachts The new Columbia Yachts, started by Dick Valdes' son Vince, with great historical information on the original company, here, and the Columbia 50, here.
Columbia Yachts Owners Association Founded 1997 by Eric White. Lots of great info. Latest entry appears to be 2012 but most content appears to be pre-2008. Columbia 50 information and owner's registry.
Columbia 50 Cruising Club was a website that was up for a few years, went defunct, and then ceased to exist altogether in 2004. After a 9 year hiatus it was reborn in response to this site, subsequently even copying our name! Archives of the original site may nevertheless be of historical interest:
Rhodes Reliant and Offshore 40 Sailboats "This site is the web face for a network of owners of Rhodes Reliants, Offshore 40s, and Empire 40s, sailboat designed by Philip Rhodes and built by Cheoy Lee in 1963-76."
Tartan Owners "...communication, sailing participation and a sense of community among owners of Tartan yachts."