While most colleges no longer require interviews, many “strongly recommend them." Certainly, having an interview is a good way to show admission committees that you are indeed interested. For those who can't get to campus, there are often interviews offered near your home. Some colleges are now interviewing via Skype or other Webcam options. Check college Web sites or call the office of admission for details.
However, if you are compulsively shy and feel that an interview could actually hurt you, there are other ways to highlight your interest in your target schools, and an interview may not be the best bet. In general, the more competitive a college is, the less the interview “counts." However, even at the pickiest places, a really super session (or a totally awful one) can sway admission decisions.