Stabilization is not a simple task so the software is going to need some work to get a good result. iStabilize (see link below) is often recommended for video stabilizing work because it is a simple and user friendly piece of software for a complex task - the quick intro documentation is only 15 lines long. There is a standalone version or an iMovie plugin version.
Alternatives would be Magic Bullet Steady (around $200) or SmoothCam which comes with Shake ($499.00) or Final Cut studio ($1,299.00).