I don't think there's a way to get skins for the 'lil buc'. Maybe there is, but I think you need to get an elite ship first.
After you get that, it depends on what skins you want.
You get skins from:
Bonus Maps(approx 25%-50% each map, but after acquiring the skin you may get smoke bombs, or teleports, or the 'all critical damage thing'. These rewards are not usually recommended.)
Add-On Content(common if you can read foreign languages/use the 'translate' function on your browser well)
TreasureBox(effective for some; never has been for me. But, I've only used approx. 2k keys)
There may be other ways to obtain these skins. However, these are the only ways I've ever gotten them.
Hope this helps.
Last edited by SemiAngryBlackBeard : 02.06.2012 at 04:27.
Reason: I wanted to make sure the last letter of all "bold text" was 'not bold'