Brian is a keen narrowboater, and has his own site.
This group supports the owners of working boats.
The Steam Boat Association of Great Britain helps preserve and operate steam boats
Canal Boat Holidays and Narrowboat Timeshare Rentals, enjoying the heritage of the Inland waterways canals and rivers
There's one narrowboat in Blackstone, Rhode Island, USA (which just happens to be twinned with Amber Valley) which has its own website.
The NABO is an organisation to look at things from the point of view of boat owners.
If you own, or are interested in, a trailable boat - the Wilderness Boat Owner's Club is a useful place to start.