The post on InstantShift list a 88 Ultimate Round-Up of Photoshop Photo Manipulation Tutorials, they are easy to follow and cool.
Below are few examples
Dazzling Dance Photo Manipulation
The Making of “Constant Slip”
Create a Photo Manipulation of a Flooded City Scene
Create a Stunning 3D Liquid Explosion Artwork
Create frozen liquid effects
Awesome Avatar Transformation
Create An Amazing Alien Invasion
Age Progression
You can read more and try them