WHERE ARE ALL THE CANNONS???

I need 3 cannons and I can't find them anywhere, Im getting a headache looking for them, If anyone knows where they are, please help me, Thank you all,

There are two shipwrecks, you need to search both. Also, there's a guy in the Mercenary Camp who gives one to you if you speak to him. And there's a guy on the docks who will give you two if you're reputation is high enough.