I've always had dry skin (it's a family genetic issue) - when I was a young child, none of my classmates wanted to hold my hand in the crocodile line - they said I had "elephant skin." I remember crying as a teenager than no one would ever love me because of my dry skin with eczema. I spent years trying different creams, potions and lotions... and was eventually diagnosed as being allergic to cow's milk. After cutting it out of my diet, I lost a huge amount of weight and became anorexic (another family genetic trait).
It took until I was 40 years old and a move to a hot, humid climate to resolve the problem for the most part! My skin is wonderfully soft, but I can still get patches of dry skin/eczema and my feet still crack and bleed when it gets colder at night.
In terms of effective products, Weleda had a wonderful moisturiser (now discontinued) that was excellent - light, nourishing and really worked wonders and of course, it was made of natural products. Now I just use E45, but sometimes even that isn't available on my tiny island home. I've used natural aloe instead - it smells weird, but it really does the trick!