I've helped more than one person find a job they enjoy (including myself) with a few specific networking tips. These work whether you're in college, or have been working for twenty years.
First, figure out a general idea of what you'd like to do. Then during conversation with friends, find out if they know anyone who is in that field, or even better has a very similar job. You'll be surprised how many people know someone who does something similar to what you want to do.
Next, ask if your friend can provide an introduction to that person. When you get to e-mail or speak to that person be very upfront and honest about the fact that you're interested in what they do for a living, and you wonder if they'd be willing to meet so you can "pick their brain" a bit. Offer to buy them coffee or lunch. It is extremely unlikely they'd have you buy them lunch. Either they'll buy you lunch or coffee, or you'll buy them a simple cup of coffee.
Now here's the key. In addition to leaving your resume with them so they can review it, and even make a suggestion or two, ask them if they wouldn't mind if you stayed in touch with them. Then, without being a stalker, send them an e-mail or give them a call from time to time. The most productive ways of keeping in touch are first to send them an updated resume if you make any changes, and second (this is a good one), keep an eye out for any news articles about their company. Nothing says you're interested like mailing an article, or e-mailing a link, about their company with a quick note that says why you found it interesting.
Eventually, as that person hears of something either in his company or another, he or she will think "Hey, that Joe Smith has been pretty persistent. I bet he's be perfect for this."