Ben Casnocha has written two excellent posts about how to successfully network with people: "It's Too Late to Get to Know a Fortune 500 CEO" and "To Find Good, Underrated People, De-Emphasize Popular Filters".
The point of the first is that if you want to know important people, you have to get to know them before they're important. This means you have to invest time in relationships with people you think may become important in the future.
The point of the second is that you'll be much more successful meeting "good" people (not just important people) if you don't use the same filters that everyone else uses. Everyone wants to meet the beautiful girl and the rich man, so they won't have time for you. He recommends cultivating interest in qualities that don't match these popular filters.