It's even harder when you don't have a proper reference. I'm not talking about hand positions, I'm talking about the subtle differences in things like the lengths of people's fingers and the way the base of the thumb is shaped. I can't seem to find any good, concise resources for that sort of thing, so I want to ask for some help. Just taking photos of my own hands won't do.
Can you guys take top-down photos of your hands resting on a table or some flat surface for me? I'm mostly looking for palm-down photos right now, but if you want to take some palm-up ones too that will be helpful later. It doesn't have to be high-quality, the important part is just that we can tell the shape of your hand. I took one of my own hand as sort of a guideline: http://68.media.tumblr.com/fc128dab081b685e466513313479f214/tumblr_oljmgj8qif1r6lybto3_1280.png
As an extra, I'm considering uploading a large compilation of the photos I'm given as a resource to help other artists. It will be uploaded on DeviantArt. Would you like to be included? It will be anonymous by default, but I can add your name and any promotional links if you would like me to.

Here are some photos of my hands! I've got really bony, large palms + long fingers combined with thin, papery skin that has a habit of showing tendons and veins orz, and it kind of shows when I use my own hands as reference (aka a lot). Seeing more variety is always useful though :D
Drawing hands IS hella hard. I will gladly take some pictures of my hands for you, if you tell me where to send them! :)
Thank you! I think it's pretty normal to be able to see the veins and whatnot. I think we just tend not to notice those sorts of things on other people's hands haha.
Thank you again! ^^
Thank you!
I'm also going to drop some better photos of my own hands here for everyone. I'll edit the one in the main post as well. Link

I'd just like to leave you a handy tip (ba-dum-ch); testosterone levels during development actually change the length of the ring finger. Usually women's ring fingers will be slightly shorter than their pointer fingers, while men's ring fingers will be slightly longer than their pointers.
Also, according to old superstition, if the pointer, middle, and ring fingers are all the same length, the person in question is a werewolf. :3