Even if you can't fathom running a local 5k, check out one man's experience running the Western States 100, a 100 mile race in the Sierra Nevada Mountains in California. Barefoot Jason Robillard has an excellent writeup of his race experience that's worth the lengthy read. It's inspiring what the human body can achieve with training, friends, and most importantly, a strong will.
As for yours truly, my marathon training schedule started this week, so with me luck! I'll be sure to give plenty of updates on my Marathon page!