Hi Susan,

I used the FIRST Marathon Training Program with great success. Here is their 1/2 Marathon Training Program. It's a 3-day-a-week program, but keep in mind that you are running HARD on these three days.

Good luck to you!

http://www.furman.edu/first/Half%20M...%20Program.pdf

P.S. Make sure to figure out your pacing for the workouts (there are different tables and such on the website). Pacing is a key component to getting all you can out of this training program.