I know there was a book in 3.5 that centered on naval campaigns, with classes for ship captains and rules for Narrative naval combat. Has that book been updated for 4e, or are there any other books in 4e with similar rulesets, or has someone got some homebrew rules that cover the same ground?
The core of the naval combat is from his basic combat rules (reproduced here in case the site goes down again):
Ship-to-ship combat plays out on a standard 1-inch-square grid, but each square represents roughly 100 feet (20 squares at character scale). Each ship occupies a single square.
Initiative: At the start of ship-to-ship combat, each captain rolls initiative. A ship’s initiative modifier is the same as its captain’s (+0 if the ship has no captain). Movement: A ship moves its speed before and after taking actions (described below). If the ship has less than minimal crew, it moves at half speed.
Crew: A ship with less than minimal crew moves at half speed and loses 3 actions per turn.
Bloodied: When a ship is first bloodied in an encounter, one of its weapons (determined randomly) is destroyed. While a ship is bloodied, the ship and all creatures aboard take a –2 penalty to attack rolls.
Actions: On its turn, between moves, a ship gets 5 actions (–2 actions if its captain is absent, helpless or dead, and –3 actions if the ship has less than a minimal crew). Actions include making a skill check to gain a tactical advantage, firing a shipboard weapon, and ramming. As a matter of protocol, the captain usually decides how many weapons to fire versus how many skill checks to make on a ship’s turn. Ramming is a special action, described below.
This may be related to the question: Fantasy adventure modules with naval adventuring
Not only are rules for sea campaigns offered, but rules for including water environments in land-based D&D campaigns and dungeon adventures are also covered.WOTC
Besides extending the standard classes with seafaring skills and spells and such, it adds several prestige classes: Knight of the Pearl, Legendary Captain, Leviathan Hunter, Scarlet Corsair, Sea Witch, Stormcaster, and Waveskeeper.
The narrative naval combat method is detailed in chapter 1. The first included encounter The Sable Drake is very verbosely described and seems to illustrate this method.
Sadly, I'm unable to find any mention of a 4th edition release date. :-(