Why does an author need an agent? Aneeta Sundararaj interviews literary agent, Janet Grant:
The publishing world is an ever-changing universe, with personnel changes and publishing houses buying other publishing houses. It’s almost dizzying to keep track of all the changes. A literary agent is like a still-point in a turning universe. Once you secure an agent, that person will hopefully guide you through your entire career, helping you to decide what you’ll write next, placing your work with the appropriate house, and dealing with the business side of publishing, which frees you up to concentrate on the creative side. And when things go wrong—as they inevitably will—your agent is there to step in and to help resolve the problem.Do also check out Janet Grant's website.