The WIP's here on DA are very valuable, but I've found watching other artists work (on video) and video-tutorials to be most helpful - since you really get to see how it's done then.
So, I'm sharing the good ones I found (and I hope I can add more and more links as people reply - I will update my Journal entry of this same message with those links, since I can't edit a news article.)
I've really learned a LOT from these and I'm not even done watching them all
Drawing the human body from your mind. (Human anatomy. Starts with a nice simple stick figure, but quickly moves on the skull.)
Excellent excellent tutorials, I can't give this guy enough praise.
He might have some trouble with some English words every once in a while, but he really explains it all very well.
When you've finished this, your people will never look 'run over' again, and you will be able to draw people, from your mind without any reference, and from any angle you want.
(I'm at lesson 20 now, of 227, so I've got a long way to go, but it's FUN! I bought the DVD set by the way, he does ship abroad )
RivenPhoenix's blog [link]
Since watching online is not as easy as watching on your computer I uploaded the first 10 lessons to Sendspace. The rest as YouTube links up to lesson 30.
Lesson 1-3 [link]
Lesson 4-6 [link]
Lesson 7-10 [link]
Lesson 11 [link]
Lesson 12 [link]
Lesson 13 [link] replace smiley with = p without the space
Lesson 14 [link]
Lesson 15 [link]
Lesson 16 [link]
Lesson 17 [link]
Lesson 18 [link]
Lesson 19 [link]
Lesson 20 [link]
Lesson 21 [link]
Lesson 22 [link]
Lesson 23 [link] replace smiley with = D without the space
Lesson 24 [link]
Lesson 25 [link]
Lesson 26 [link]
Lesson 27 [link]
Lesson 28 [link]
No affiliation, but if you like them - buy them all. They are well worth your money. I think it's all 5 DVDs for 45 dollars plus shipping.
Watercolor on the Painting and Drawing channel on YouTube: [link]
I'm going to try this one very soon:
Trees & Woodland part 1 [link]
Trees & Woodland part 2 [link]
Trees & Woodland part 3 [link]
Pastels with Colin [link]
Great skin-color tips (and other tips as well)
Some tutorials seem really great.
You have to buy the full version though, which I haven't done because I don't like paying for "6 month access" and not getting a copy of the thing on my computer for when I want to rewatch it after the 6 months. (And maybe 6 months should be enough to never-need-to-watch-again, but I just don't like it).