Think I posted my blog page on the RL marathon page? Can message it to you if not. Really, you have to think long term about this, 6-12 months.
Stretches after fine, but I would do planks and running specific exercises on a different day for best benefit. So you get the best out of running, and best out of exercises when not tired...
Are you a member of a gym, or perhaps a circuit class/ boot camp nearby? They would really help, anywhere from £2 to £6 a session, quite a few good ones around Liverpool, Sefton park, childwall & wavertree.
Edited: 08/04/2012 at 16:01