Well, happy news. Green Ronin has just released a Web enhancement to their Buccaneers of Freeport book with stats for many pirate captains! It’s available in 3.5e and True20 variants.
Buccaneers of Freeport and Cults of Freeport were odd book choices – they were statless. This was during the Mass D&D Confusion around the 4e launch. For Cults, that was kinda OK, but with Buccaneers it really hurt- character backdrops for a bunch of cool pirate captains, but no stats. Well, they have now published the stats, for free! Oh, and the stats for Cults, earlier on.
Download the stats, then consider getting Buccaneers and Cults as they are fine books (and often quite on sale…). Get cranked up for the pirate holocaust that will come soon with the S&S AP! All the Freeport stuff is great to mix with Golarion, in Reavers I used the entire Freeport Trilogy mashed up with Second Darkness to good effect.