*Wanders in* Ooo, cool!
Hmm. Since a few people have already asked me if i have any tutorials, which sadly i don't, maybe i can put out a couple tips on things that i've found really helpful, who knows, they might be useful to someone else too. *shrug*
* The "Magic Wand" selector is your friend. When cutting/copying, coloring, erasing, moving, and any number of other important things, I find it really helpful to use the magic wand. It's my staple tool - looks like a dandelion puff on the tool box, if you don't know where it is. It selects by color, and you can select how specific or vague you want the selection to be by the number box when you're using it.
If you're daring or good with the mouse, also try the Lasso tool for freehand selecting.
* Coloring: Don't just brush on color with the pencil or brush, since sprites rely heavily on specific areas of flat color to show shape - use the Hue and Saturation command (Enhance> Color> Hue and Saturation) to CHANGE the color of your selected (with the wand or lasso or box) area. "Colorize" is useful for this. Make sure to check all three sliders to adjust the color, especially the saturation.
* Layers: don't be afraid to make several layers when puttin' things together. You can merge them later, or wait until they automatically merge when saving as a GIF.
* Swapping Parts: try swapping different parts from sprites to create new things that better express what you're going for. Heads, limbs, eyeballs, especially hair. Be a mad scientist. Also look for specific shapes for other things you need in other sprites - being original is good, but a chunk out of another sprite is already going to have the right dimensional shading so you don't have to figure it out yourself. Be creative, just look at random shapes. Somebody's hairbow could become the assault rifle you're looking for.
* Transparencies: be careful with transparent brushes, since a GIF will sometimes flatten your nice hazy color into a funky-looking solid one. Most sprites are all about flat, sharp areas of color, not blending and shading. Keep the edges of your sprite clean - also, try not to rotate pieces by hand too much, it'll make 'em fuzzy - 90, 180, 270 degrees only will keep 'em sharp.
Here's some links that may or may not be useful and might have already been posted, i forget. I got 'em originally from other spriters, some have the big ones i use, some have small animated ones that are also fun.
>_> ummm.... yes.... and stuff. Go! Fly! Do art!