My hair likes protein
it's just that coarse hair GENERALLY doesn't like proteins. I can't say for certain that your hair won't go well with proteins. But it's all trial and error, really. If you don't know whether your hair likes proteins or not, you should just try sometime. It's good to know as much as possible about your hair, and what it likes/dislikes. When you've used proteins and your hair feels like straw, and frizzy and dry, then you're most likely protein sensitive.
I recommend Kinky Curly Knot Today as a leave in btw
As for buying hair products online, I really recommend
iHerb.com - Vitamins, Supplements & Natural Health Products. GREAT webshop, they have an impressive collection of natural conditioners, shampoos, oils, stylers. They also have brands like Kinky Curly. Their shipping costs are REALLY cheap and I've only had good experiences with them so far.
Good luck!