Ships and more ships

Beyond the Black Gate and RPG Corner had a good series of post on ships

Beyond the Black Gate has

A little info on Ships
More on Ships - the Crew

RPG Corner has

Ships of the Wilderlands

For my own contribution I would like to point out Columbia Game's the Pilot's Almanac

It may be a Harn product but the articles on Pilots, Crew, Maritime Trade, and Shipwrights present a seafaring setup that are comparable in scope and in simplicity to Traveller's rules on Spacecraft and trade. While the Port Almanac and Charts are Harn specific you can use them to get a sense of what stats to assign to the various ports of your setting. The only downside it is a bit pricey.