cool, thanks man! i have something that i recently drew but it's pretty stylized, i'll have some of my observational sketches up later hopefully
[hider=img][img=http://37.media.tumblr.com/272e03e0639fe3c28c0deb7c54777b44/tumblr_n9c8nmkKwl1qjma2yo1_500.png][/hider]

@Totts
the references that sherlock put on the front page are some good resources, but really, you just need to draw, the more you draw the better you get
observational drawing is, in my own experience, the best way to get better. even if you aren't going for realism learning how things work will improve your art in general
of course if you want to do something specific, like hand studies, you can always google these things and get a million resources for you to use
if you have something specific youre interested in drawing though, i could try and help you find more on that o: