On Denny's Puzzle Pages, there is a layer solution with many pictures. He also has solutions for the pocket cube and Rubik's Revenge.
Jake Olesky's CubeSolver is a well documented step-by-step layer solution.
Skip Lawson has another layer solution with cool pictures showing each move.
On the official Rubik's Cube web site, they have two layer solutions, old and new, posted. They also have links to other solutions of 2x2x2, 3x3x3, 4x4x4, and 5x5x5 Rubik's Cube puzzles.
Lars Petrus describes the speed solution that won him the Swedish championships and got him 4th in the world championships in Budapest. This page features a great Java applet that animates each sequence.