Basikboy, there is a case currently in the courts over the use of a copyrighted photo, and an artist's "derivative" work based on this photo, that you might be interested in reading about.
Shepard Fairey is an artist who used an AP copyrighted photo of Barack Obama to create posters and other merchandise, without permission from or attribution given to or compensation for the photographer who took the photo. Fairey has profitted from the use of the image and from the use of Barack Obama's name to sell his merchandise.
The case is between Shepard Fairey, Obey Glass Art, Inc., Obey Giant LLC, and Studio Number One, Inc., and The AP (who owns the rights to the photo in question), and it argues some of the copyright issues that you are inquiring about here. Obama's likeness, although potentially a publicity rights matter, is not involved in this case, although if the photo were of another public figure or celebrity, the marketing of products using the public figure's name and image could be central to any action (California's Governor brought a publicity rights action, for instance, over the use of his image for Bobble Head dolls).
The AP has stated that licensing "is an important source of revenue for content creators" and, although they attempted to enter into a license agreement with Fairey after the infringement was discovered, to avoid costly litigation, the suit continues in the court.
When using celebrity images, especially those taken from a copyrighted work, you are at risk of publicity rights lawsuits and infringement lawsuits. Permission should always be obtained first before attempting to profit off anyone's intellectual property rights or publicity rights.
