@sonny6killer: Just jump in at the start of a new arc (or a whole series most DC series are currently at just over 40, Marvel don't really get over 40 any-more before a re-number) with a character you know like Batman, Wolverine etc. Then work from there other characters and ideas will show up and if they interest you seek them up. Gradually you'll end up following them like you do games and you'll be aware of what's coming out and if it interests you. Superhero stuff seems intimidating with the massive amount of content published but if you just jump in it all works itself out. The hard part is just going for it. The comic vine wiki is also helpful for any characters who pop up you don't know. As regards non-superhero stuff again just jump in although due to the more long form of a lot of those stories you may want to start at number 1.
Just find something you like or that interests you and jump in.At least that's how I got into them around 2 years ago and now I follow it.
@sergio: Marvel unlimited is great you can read through old massive arcs for relatively cheap. I've read all the old marvel cosmic stuff, so much easier ad more convenient than tracking down the physical books. The newer comics are even added as soon as 2/3 months after release. Keep an ey out for offers regularly do stuff like first moth for 99p