For those running their first marathon I would recommend any one of the marathon training groups that you might find.
Philly Fit Training Programs - 2007 Might be a good one. You have a long training run on Saturdays with an appropriate group, then a schedule to stick to during the week. They also have nutrition, stretching and injury prevention seminars.
Running with a social group helps make you show up and stick to the routine. The support of your running peers through the long runs and race day are critical. Who knows you might meet some very nice people. Good luck!