I have been running for a few years now, but am targetting a marathon for the first time.
I have started on the Beginner Marathon Program for a Marathon run in Jan '13 and had a few queries
1) If my long run is on a Saturday, what would be the ideal day for a leg workout (squats, leg-press, etc)?
2) Any suggestions on how I can do Fartlek/Interval runs on a treadmill?
3) In the past, I have got back pain while using an incline of more than 1 unit - can I achieve 'hills' in any other way, maybe climbing stairs?
I have no idea about treadmill options, so I would encourage outdoor routes as much as possible to best prepare for your marathon. Middle of the week might be a good target for strength cross-training if your LR schedule is typically Saturday. Also, try and work in some other events this fall (10k, 15K and/or a half). Those are usually good opportunities to push out the limits and stay motivated for the full.
Congrats and best wishes.