Skulls and Shackles
This page will have links to important rules of this campaign. All credit goes to these sources and Paizo as this campaign wouldn't be as fun or would even be made without them.
Continued Naval Combat: http://www.d20pfsrd.com/gamemastering/other-rules/ship-combat
Naval Siege Engines: http://www.d20pfsrd.com/gamemastering/other-rules/ship-combat/naval-siege-engines
Spells in Naval Combat: http://www.d20pfsrd.com/gamemastering/other-rules/ship-combat/spell-effects-in-naval-combat
Ship Customization: http://www.d20pfsrd.com/gamemastering/other-rules/ship-combat/vessels
Fleet Combat (Mass Naval Battles): http://webpages.charter.net/tedsarah/Pathfinder/srd/additionalRules/NavalCombatMass.htm