For generic kicking and fighting spritesheets, I'd say look for streetfighter sprite sheets. Ryo is pretty much as stereotypical as you get 'em. (Because he's very old, not because he's poorly created!)
For looking at level design and where to put things for certain games, I would give this site a look:
Though there's one thing you can also do that's probably the best thing for you to do, and anyone else wanting to do any kind of work, is to do your own original research. Play same games, map out the levels, mark where things happen and what kind of things they were. Things like that, and you'll almost certainly gain an intimate knowledge of level design.