A very helpful supplier of model boat accessories, motors, r/c etc - all the r/c and motor equipment for the models in the manual came from this supplier who were very helpful and quick.
Model sailing yacht sails and fittings.
Blackburn Model Supplies - wood, tissue, dope etc.
The Model Dockyard - suppliers of hardware, kits etc.
JMP Balsa and model ply supplier.
Nice site developing model yachts - if you want a one off model (static, working etc) made to a high standard based on a Selway Fisher design then contact this site.
This is just a start and I am more than happy to add more links to model boat materials suppliers, clubs, associations etc. Please with any links that you wish to add to this list
A vibrant model boat club.
Tony Holt's model boat page - an excellent site from an enthusiast with a very good contact's page plus loads of photos of models boats.