I need help!!!

I am trying to make a magnetic generator that lights a mini led and really don't know how to find a mini generator.I looked online for 3hrs can any one help. also I don't know what size generator i'll need to light up the bulb.

Any brush-type DC motor with a permanent magnet stator should act as a generator if you spin the rotor.

The size (I assume you mean physical size and weight) isn't important. About any motor inside a cheap toy will work as a generator. You just need to make it goes fast enough (and correct direction) to make a connected led to light up.