Does anyone have any suggestions on how to model naruto characters? I'm currently using Blender, but I can't really use it too well.

Learn to use it better. [smile]

Modelling is something that people typically spend a few years getting good enough to make quality models. It's like anything else in art: it takes a few years before you can paint or draw well. You can't expect 3D modeling to be any easier.

I'd suggest taking some classes, or finding some good books, or finding someone to give you lessons, or look for some tutorials online.

But expect it to take a long time before you're making something really good.

-me

It's usually easier to model something of your own imagination instead of trying to conform to someone else's visual style.
It also lets you avoid cease and desist letters and IP conflicts.

i'd suggest doing some environment modeling before attempting character modeling. though i do know one professional 3d modeler that started with character modeling first, but that is a rarity to be able to do well.
that and, as has been said, 3d modeling takes quite a while to get good at.

Does anyone know any good sites for Blender documentation?

There's some links on Blender's homepage here.
One of them is Blender 3D: Noob to Pro which seems to be popular.

If you're modeling a character, the easiest way to do it is to bring front and side view images into your 3D program. Some programs will allow you to set them as backgrounds to your cameras, but I can't speak for Blender. If not, maybe you can fake it with a textured plane.

However you do it, the idea is to have an exact guideline for what your character should look like, from at least two views, and model on top of that. It doesn't make it easy, but it certainly makes it easier.

A great free modeling program for beginners is Game Space.
Caligari GameSpace

There are also some great tutorials for GameSpace on 3D Buzz.com.
3D Buzz Video Training

Try and adapt the jone of arc tutorial to Blender then you could prob tackle a naruto character.

http://www.3dtotal.com/tutorials/max/joanofarc/joanmenu.asp

Don't forget about Poser if Blender is too much for what you want to do.

The demo can be found here

Example gallery with 6 pages