Where can I find some comics on line?

OK I’m looking for some comics books on Alien limbs but I don’t know where to look. I am trying to draw some Aliens where can I find some comics books on Alien limbs? I want to know every thing a bout them like what do they eat? how do they walk? How do they fight? The more I know about them the easier it will be to draw him or her in action. So that I can come up with my own characters.