What color is your hair? What animes are you into? What have you seen? Honestly I wouldn't suggest cosplaying as a character from a show you've never seen. I dunon, maybe it's just me but that'd be weird
But here's some suggestions anyway..
Aye, Naota, like Negima said, would be pretty easy.
Sagara Sousuke from FMP! is easy enough. Black pants, brown shoes, white dress shirt + the Japanese schoolboy coat thing.
Lupin III. Everything can be had from going to thrift stores.
Nabeshin (Excel Saga). Same outfit as Lupin, just with an afro.
Heero (Gundam Wing). VERY simple outfit. Most people probably wouldn't even recognize it.
Quatre (Gundam Wing). Would be a pretty simple costume to do, though he has blonde hair (most of the characters I've listed have dark hair).
Hideki (Chobits). Not really worth doing unless you're with a Chi cosplayer though.
Luffy (One Piece). Very simple, easy to do as long as you can find a good enough hat.
Sanji (One Piece). Again, simple enough to do - blonde hair again.
But really, give us some more to work with, like answering the questions I stated above.