When I was first starting to try and draw people and such, one place that I visited a lot was
this site. It's, like, mostly manga tutorials, but I found that most of what she teaches is pretty universal. She even has entire tutorials just on hands/eyes/muscles, and she presents all tutorials in a step-by-step system.
Most drawing books I've found seem to try to teach very specific styles rather than general guidelines (probably because the artists who make them have very specific styles they use), so I've never really seen a lot of point in buying a lot of books.
One thing I did when I first started drawing was to take pictures of my friends and then try to draw them, translating the small pictures into 9x11 sketchpad pages. It helps you get used to proportion and studying different facial structures, and gives you a chance to work on a subject that you know well enough that you'll notice if you're drawing's a bit off.
One thing I've always found useful to remember when drawing, at least when you're starting out: don't try to draw the person you see. Instead, try to draw the shapes of what you see. Most artists eventually teach themselves to do this unconciously, but many beginners will try to draw the person rather than the shapes the person's made of, and the former is much, much harder than the latter. My HS art teacher told us to draw images upside down, to learn to associate with shapes and lines rather than objects.