Cream Puffnut
You don't need tutorials; often they don't really help at all (I know, I tried). You need to look at real hands and learn how they work. Use your hand, images of hands, other people's hands (of all ages!). Try to understand it for yourself; that helps you gain a MUCH better knowledge of it than looking at tutorials since only you understand the way you learn things.
i do try to draw my own hand and images of hands, but i sometimes don't know where to start from there. for example when i start a drawing and i get to the hands, i make the hand pose i want looking for, and i just sketch the shape of it which i always make mistakes at.