I stumbled across an interesting resource just now: Wet Canvas!
Lots of "channels" with advice and inspiration for tons of different art disciplines and media...and nearly 100,000 members from whom to learn. Membership is free -- and gives you a $5-off coupon at Dick Blick Art Materials.
Amazing what I can find when I really should be working.
I got up the nerve to mess with a little color. The paper's white, but I took the photo in incandescent light, which my dying camera reads as even more yellow than you see here (oh, and love the little shadow in the upper right corner on all my photos...)
In my voracious (and distracting-from-work) reading about all things sketchy and brushy lately, I caught what sounds like a cool hint:
Draw something upside down.
No, don't flip over, pencil in hand.
Turn a photo or drawing you want to sketch upside down, and draw what you see. The idea is that you will see the forms that are really there -- the way you used to see as a child, before logic muddied things up. It's drawing without assuming the forms add up to anything you've learned to recognize.