Hi Jane, I am also new to running and completed the Edinburgh Half Marathon last May. If it is the same route you will pleased to know it is flat! What i found very helpful was marathonrookie.com as it has a beginner 10 week training schedule. Have a look at it and see what you think. I have since ran the Bristol Half Marathon last September and hoping to run the Brighton Half and then the Liverpool Half in the next couple of months.  So I am hooked as well although my times are very slow, I am 57 years old so my joints are creaking a bit! Best of luck Jane and hope your training goes well.