Okay, so I'm just starting out here so pardon if this sounds a bit confused...

I've heard tell of books on different parts of the body and pictures of people in different poses (like sitting, standing, arms folded or just bent, legs crossed, etc). Are there any that people here would recommend?

I own Anatomy for Artists by Sarah Simblet and John Davis - it's pretty good. It explains how bones and muscles work, and has lots of photographs for reference.