I've decided to post my training schedule here for your perusal. I've actually posted 2 schedules, version 1 and 2. Version 1 is the training plan I created for myself after researching a couple of other plans I found on the internet. Version 2 is the plan as it developed in reality. For example, I had to change a number of my training days to other days due to time conflicts. This is an important point, I would recommend anyone training for an endurance event put together a training plan. However, you have to be flexible enough to be able to adjust the plan from time to time to be able to fit in other aspects of life. This doesn't mean missing sessions but rather re-scheduling where necessary.
The plan I used lasted 16 weeks with 4 runs per week. 16 week plans are fairly usual and are designed to enable you to train to the level required then taper with enough time to be in peak condition for the event. I'm sure there are some longer plans and maybe some shorter but 16 weeks sounded like it would suit me, not too long but long enough to bring myself to the right condition. Its important to remember that prior to embarking on such a plan it is necessary to be running base mileage for at least a couple of months so that once you start the plan you are already running 20 - 30 miles per week. Attempting to start a specific plan prior to running base mileage will, most probably, result in injury so beware.
Most plans will have 5 runs per week scheduled, I decided on 4 because I cycle at least 4/5 days per week to and from work. Thats between 80 and 100 miles. Also I occasionally head out with my cycling buddies at weekends for a 35/40 miler so I figured I'd keep the runs down to 4 days per week in order to not burn myself out.
As I mentioned in my first posting although I am fairly experienced as a runner this is my first marathon and I'm no training expert. What I write here is only my opinion based on actual training that I have done, it seems to have suited me well. (I'll know for sure when I've finished the run and see my time). If you're going to train for your first marathon you'd be well advised to get a check up with your doctor before embarking on any kind of training plan.