I have had mild success with okcupid with very little effort. I wrote my profile, answered some questions and just sat back and let people message me.
The reason I "just sat back" and waited for women to come to me is
not that I'm an arrogant jerk, it's that like Scott said, there are too many men. I agree with
this guy's (youtube video) view on online dating. Let women come to you, or be ignored. Either way it's better than being insulted by women that are so sick and tired of being hit on by jerks that they can't recognize a nice guy when they see one.