Hope I got this right, it sounds like you're asking about the stock camoflage paint schemes. If you got it from the 'u-play launcher' then that is the 'downloadable content (DLC)' I was talking about.
Really easy: when you're are in the Uboat pen before a mission just click on old mate with the moustache where you get your torps and equipment upgrades and you'll find the new paint jobs under the 'camoflage tab'.
More become available as you complete missions.