Runner's World has a great series of articles in their recent "Marathoning 101" section.
Marathon coaches measure success not by how many runners they get to the starting line, but by how many of them finish. With the help of 10 supercoaches who have gotten more than half a million marathoners across the line, we've collected the best tips, strategies, and training plans to prepare you for your first--or fastest--26.2-miler this fall
Most people think running a marathon is out of the question. But, it's such a fear thing. Once you get out there and learn how to push yourself, learn how therapeutic that running long distances can be, it's awesome. I love to see people who haven't been into exercising start running and find something that works for them and within their schedule!
I am concerned, though, because I don't think that many runners spend enough time in training before they run a marathon. They train to do the distance but not the stress of a marathon. They complete the marathon but do so with pain and injury. Neither pain or injury need be part of the marathon experience if they would run 15 or more miles once a week for an additional 6 months to a year before they run a marathon.