Comment From the Skipper (Score 0) 340
The wind at your back and a star to sail by.
Seriously though, I would log onto Cruising World Magazine's website and start reading through their back catalog for articles on how to prepare for blue water sailing.
I would have at minimum: gps plotter with charts, radar, vhf radios (one for boat, handheld for dingy), ssb radio, cell phone, laptop, ipod, watermaker, and good instruments for wind/boat speed, etc. Make sure you have redundant equipment that can work without electricity or handelds that work on local batteries.
By the way, don't bring a gun, unless you don't want to be allowed into any port. Guns are forbidden in 99% of countries if you are entering by boat and they will immediately make you leave if they don't throw you in jail first. Bring a Crocodile Dundee knife, instead.