I use Ouidad. It's a company that on,y makes curly products. It's ridiculously expensive but Jon makes me buy it because he says he'd rather shell out $30 for shampoo and conditioner than listen to me cry about hating my hair. it really is the only thing I've ever found that can control my crazy curls.
I have been using this, Simply U, for a while now. It's sulfate and paraben free and while I could be imagining it I really feel like I loose less hair in the shower since I've been using the sulfate free. Sulfate free shampoos don't suds up or create lather as much so it feels a little different when shampooing but hasn't bothered me at all. I also really love the price point and the scent of it. I get it at Walmart for under $6 each for the shampoo and conditioner. I use the volumizing b/c I have fine/thin hair.
I use Earth Safe and sometimes Dessert Essence Organics. If I run out of shampoo I'll use Dr. Bronners (which I use on DD). I'm all about the "everything chemical" free shampoos. And since DH started using it a few years back, he has such thick luscious hair - he has definitely noticed the difference! It is quite pricey - but I know other people that pay similar for chemical ones, and I just don't wash my hair that often