According to Wikipedia, a photo-manipulation is the action to alter photographs images to create an illusion. Clearly, there are manipulations of all type. There are simple manipulations, or totally elaborated manipulations, created by recognized designers. The important fact is that if you want to learn you can do it with the help of the Internet. Some knowledge of the Photoshop, time and patience.

To start, it will be a good idea if you visit one of the latest articles of SpeckyBoy, where they compile 28 incredible tutorials of photo-manipulation and with professional results. Although the idea is that you can experiment with its own creativity, the best thing is to learn via Internet. Then practice, know the techniques that they are using, and once you feel comfortable, try to generate your own designs.