I just came across this interesting video on http://www.dvafoto.com/, where National Geographic photographer Sam Abell talks about making pictures for a story on the life of American cowboy painter Charles M. Russell.
I found it fascinating listening to the lengths he went to so he could get the perfect shot of bison skulls. In an age where people take digital photos every few minutes, it's very unusual to hear a story about one photograph that was a year in the making. He mentions near the end of the video that although he took roughly 25,000 photos for this story (all on film) only eight pictures were used in the final article in National Geographic magazine.
You can see more of Sam's work on his website here: http://samabell-thephotographiclife.com/
As well as some on the Digital Journalist: http://digitaljournalist.org/issue0202/abell_index.htm