Congratulations on taking the first step towards your dream job-searching for an internship that will get your foot in the door and give you a taste of working in the real world. Don't fret because you haven't worked in an office before, employers understand that you are just starting out. And while you might not think you have enough experience, most of what you've done, even scooping ice cream at Dairy Queen when you were 16, is important to showing that you are responsible and driven.
You are also going to want to include a cover letter stating why you would make an awesome intern, and show them you're a great fit for the company. For samples of cover letters, check out Jobsearch at About.com.
Internships are excellent ways to gain professional experience. They introduce you to professionals in your field and act as great mentors. Internships prepare you for your transition out of the life of a college student and prepare you for what life is like after graduation. Be sure to make the best of your time as an intern, in many cases companies fill entry-level positions with candidates from their internship programs.