Thanks for all the comments guys, they really brighten my day.
Iron Chef: Which school did you go to? I'm still at school (in year 12) so I did do them while I was at school, but not actually in school, if you know what I mean. I don't draw stuff in class, because I'm trying to make sure I get really good marks this year, my final one!
Mrs Bender: That's not a bad idea! A sketch site would be cool, although I tend not to draw much apart from Leela... unless it's for school (I do TEE Art). I doodle a bit, but never do proper planned drawings, as I quickly get bored of doing any particular drawing for extended periods of time. I draw myself a bit though, and last year I did a B+W lino print of King St (a little coffee/shopping street in town). I couldn't scan it though, as it's too big for my scanner.
SJM: I don't know really, they just sort of turned out that way. I think it's because I tend to draw people with big, curved cheeks and cheekbones, and that's quite a young facial feature.
Dr. Jerkbird: Just keep trying and you'll get there. Everyone has to work at things to make them happen, and it won't take long before you get where you want to be. With Leela, the best thing to do if you want the Groening style is to get the feel of how she works. Don't copy her, just trace her a few times to get the hang of her face and body. Then you'll get a feel for how high the ponytail goes, how much it curves, how low the fringe goes, etc. Also, when you first start to copy, use a nice thick pen to give you confidence - the thick lines will give you a less accurate representation, which is sometimes a good thing (trust me). So trace, trace, trace and then, when you feel like you've got the hang of it, try drawing it freehand. I find it's good to have a process - mine goes like this (for Groening-Leelas):
Draw the ear.
Draw the curvy bottom part of her hair.
Extend it upwards, drawing in the two spikes and coming down to her fringe.
Do the inner fringe line, pulling your pen to about where the crease in her hair is, but a bit away from it.
Draw the two bits of hair, making sure the second one goes over her ear.
Now that was the hard bit - once you've got that bit in, you have a template for the rest. Next,
Draw in the eye behind the fringe, add eyelashes and pupil.
Whack in the nose.
Extend a line from a point in the hair, then draw in the mouth.
Draw the lips.
Draw the neck, just two straight lines, one from halfway across the lips and the other from the ear.
Draw in the ponytail.
I won't tell you how to draw the body, because it's pretty much a normal body, so you could just practise drawing other people. Or trace her body again and again so you can get a feel for it.
Hope that's helpful, and thanks again so much for all your comments!
Edit: Oop! I forgot! At the moment I'm doing a Leela cross-stitch, so you can expect to see that up here pretty soon. It's been taking a while though, so I might get a bit frustrated with it and forget about it at some point, but oh well. At least you all know I tried.