where to buy animated characters?

Hi all

I have been thinking about creating a platform game on my spare time,
but am not very proficient with drawing the bitmaps for the character.

Does anyone know of a site where to buy already drawn characters,
suitable for a platform game? The character should be drawn in
different poses (such as running and jumping); a 3D animation would be
ok as long as it is possible to export it to another format such as
bitmap.

thanks in advance

JJ