Personally, I wouldn't suggest imitating other artists (no offence, Fenrir). When you do that, you're not really learning good a foundation, you're learning how to draw in someone elses way rather than your own way. Plus, it's not proper since the person you're imitating might be drawing stylistically, meaning that you'll only learn how to draw objects the way that the other artist sees them, rather than what they really look like.
Although drawing stylistically sounds fun, you can't just jump in and decide you're going to draw in a certain style (ex: anime). You have to learn how things really
you warp them to the style you want.You have to learn the rules before you break them.
If you draw things realistically at first, then you have a good foundation and understanding, meaning it'll be easier to develop a style because you'll know what things really look like, and you'll know how you can change them to obtain the look you want to achieve.
That being said, the best way to learn is to draw from real life references.
Pictures are okay, but nothing beats the real thing.
See, with pictures you only see the dimension that the camera sees, whereas if you draw from life, then you can see all sides of the object and understand its dimension so you can better communicate that in your drawing.
So, if you want to learn how to do character drawings, you need to learn how to draw the human (or animal) form first.
If you're doing a furry character, it's important to learn how to draw humans and animals, that way you can have more options when it comes to drawing your character (ex: giving them more human looking feet, or more animal looking hands, or an interesting mix of the two).
Like I said, drawing from pictures is good, but draw from real life as often as you can.
It's also good to get some good tutorials from Deviantart that explain how to better measure the placement of body parts or facial features (ex: eyes are usually one-eye-length apart from each other, the ends of the mouth usually meet the middle the eyes, the bottom part of the ear usually meets the bottom of the nose placement).
Sorry for the HUGE WALL OF TEXT, but I do plan to be an art teacher in the future, so I have lots to say on the subject.
Anyway, if you survived all that, here's a good tutorial on drawing furries:http://hippie.nu/~unicorn/tut/xhtml/
It's good because it also gives guides on how muscles act and are placed, as well as skeletal structure.
It's a lot to read, but there's some really good stuff and guides in there, so I would suggest it to anyone.
And if you scroll all the way down, there's an index in case you just want to look out one certain part of the guide.
Another good site is:http://characterdesigns.com/index.php?sitepage=photosets
WARNING, THEY DO HAVE NUDE MODELS ON THIS SITE.
But, they are all for artistic purposes (not pornographic).
Anyway, that site has a BUNCH of pictures of models in different poses, so it's good for practice.
ANOTHER good site is:http://www.posemaniacs.com/
This site has 3D pictures of people without skin.
Now, although it isn't really a real-life reference, it's still an excellent site, since it shows muscle placement, PLUS you can ROTATE the 3D models, which is great for practice and learning how the body looks from all angles in a wide variety of poses. I believe there's also a 3D head model somewhere in there that you can rotate to whichever angel you want....