The training plan

I have learned so much. There are all kinds of training plans out there for half and full marathons. Here's my problem. I keep switching. I started off with a nice 4 day a week plan. Fits my schedule perfectly. But then I thought to myself, I've been working out 5 days a week and I hate to mess that up. So I found a 5 day a week plan. After changing in the middle of the week this week, I'm wondering if I should go back to the 4 day a week plan. Who knew the choice of a plan was this difficult? I haven't hit the hard training yet. I'm 12 weeks out and my workouts are basically what I've been doing the past 6-9 months. Here in a couple of week though, I'll be running 5 miles a day, 3 days a week, with a longer run on Sat. I'm starting to get nervous.

On another note, I got the book "Marathoning for Mortals" at the library. I had read a comment from someone on Runnersworld.com recommending the book. And I have to say, its amazing. There is so much to learn. And I'm super excited.