You can click any images to make them larger. Links are provided in case the hot-linking fails (they also provide access to the largest available size, which is helpful for text.)

First: here are a bunch from Tracy Butler (who makes the Lackadaisy webcomic), because I love them. Some are kind of rudimentary while others are a bit advanced, and some of the information overlaps between guides, but I really love the examples and tips provided.

All my freaking love leads here.

More of my love!

Link to further information on character design! This is great! GO GO GO; what are you waiting for?

Link

Link

Just one method of potential shading but it intrigues me.

Now here's some Coelasquid. If you're drawing dudes, you might want to give this a look.

And this too. Your brain may liquefy without more detailed muscle info to go with it. A lot of this can apply to men and women, but female characters tend to be really stream-lined regardless of how detailed the males in a similar style will be. Women also tend to be curvier and they have a slightly lower (I believe, please correct me if I'm wrong) center of gravity from men, but don't let that stop you from drawing muscular chicks.

Link

Link

Various examples of the height measured in heads. This is about the proportions, namely involving how tall they are compared with their head size. Bigger Head + Fewer Heads in Height = Short and Cute. Smaller Head + Many Heads in Height = Tall and Elegant or Tall and Intimidating, depending on the body build. Too many heads tall or too many heads short and it can look alien and/or ridiculous. Keep all of this in mind when designing your own characters or making adjustments to any sort of canon character. It's all good, as long as you're aware of the outcome. The photograph examples in the link are especially fascinating. Do note that the information in the text is referring to mostly normal human characters. Obviously the MLP characters don't canonically follow this recommendation and many cartoon characters in general probably have a different sweet spot that is closer to 4 heads in height. Btw, this page has additional links to other guides on the right, but I haven't examined them. Explore them at your own discretion.

Link

This one includes some suggestions on foreshortening.

A VERY good hand tutorial. The image requests no reposting, so just click the link to see it.
And a good guide to feet from the same DeviantArt user. (Though I'm a little uncertain about a few of the generalizations, most of the rest seems pretty solid.)

Link has a little more info and links to some interesting sketches of related subject matter. Of course there are probably a million guides on drawing the body on DeviantArt, so I'll cut it short with these.

Line of Action. Some of the stuff at the beginning touched strongly on this but it's a really basic element of dynamic art.

Lines of action tend to be curves but some are more subtle than others.

Further avoidance of static poses. I think the commentary on group actions is the most useful here.

Note: Many of the following require clicking the links. Either they have a lot of text or interactive elements.

This is a flash file and it's full of some great stuff about Color Theory. Click on it when it says that it has loaded.

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This is so funand it's useful! It's a flash thing as well, hence no images. Click the various circles and links to get more information and some recommendations about your choices of color palette! It really only does one color at a time, so you'll have to just compare some of the results or select each color individually. Having multiple tabs of this open at the same time might be helpful for fast comparisons. It also offers the exact hex codes, so you can take the results directly from this site! Note that it's really set up for websites, but the color theory still works for everything else as well.

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Even better than the above, but it works in conjunction with the other two. It gives a lot of great information. Just type in a hex and go!

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Another palette suggestion site. This one is different from the above. It has links to various already grouped selections, plus it has ideas for patterns. It's not focused on just one subject, like web design. If you want a quicker idea and don't know what you want, browsing through here could help. It also gives the hex codes, so you can drop the precise colors right in.

This page explains what tonal value is.

9 Tangential Blunders

9 Steps to Better Composition

A Tutorial on Line Weight which includes some ideas for scanning line art images. Not utterly comprehensive, but handy.

Here is another illustration of line weight used in a complete image. It's more exaggerated than the anime/manga style one provided in the link above.

Please feel free to reply with more general guides and tutorials about art!

I realize that I only touched the surface, but I was doing my best to find stuff that didn't have naked people in the links.

omg i love Tracy Butler

2904498 I do most of my stuff by hand, so it doesn't look like the characters in the show do, y'know what I mean?

I love it when you post up tutorials Would you like to be an admin?

2904514 Why is she not already..?

2904498 Thank you. These drawings of yours are amazing.

2904509
One of my favorites! The web comic is equally amazing, IMHO.

2904512
Yep. Nothing wrong with another medium or another style. That's part of why I tried posting some more general guides. Although, I still think many of the guides in my other thread, here, can be useful.

2904514
Well, I could try, but I honestly have no idea how useful I would be in the long run.

2904759
Are you sure?

2904750
You evil, sexy beast.

2904736 2904803
Oh, all right. I'll do it.

(But don't blame me if someone cries Chaos and they let slip the diamond dogs of war. I'll be hiding in my bunker then...)

2904969 ... And proud of it!

Can't touch this!

2904498 Cool stuff to be sure. I dig the demon horse sketch in the third picture. Thanks for all the tutorials.

2905009
I added s'more btw. Hope they're okay.

2904498 Whoa! You went all out! Nice.

Haven't seen this much proportion refrence since college. Well chosen and well laid out.

2906168 They're all brilliant.