What's the best way to condition for long nonstop runs?
run a mile the first day then 2 the next and then 3 and etc.. and soon you'll be in great shape and leave time in between each run so you can heal
start with shorter runs, and build up to longer ones as your stamina improves. Listening to an ipod or mp3 player usually helps too
Start running. Never stop. Eventually, you will fall over and die. As you see the light slowly disappearing, consider yourself conditioned.