Back to Creative Writing School which is available as a Kindle ebook for all of £1.70.
I have to say it is one of the most inspiring and unusual How To books I have ever read, and I whole-heartedly recommend it. So do many other people - go and take a look at her Amazon reviews!
It's formatted like a school year - 3 terms, 10 weeks per term, and a lesson for each week including exercises to inspire and energise you.
Some exercises are very quick, others would take an afternoon of solid work. They all look worth doing, and I think I'm going to need to take a year off and do the entire course! Whether you're a new writer wanting to get going and learn some skills, or a jaded and faded writer getting long in the tooth, I think this book won't fail to get you up and running, producing your best work ever.
10/10 to Bridget for this one. Gold stars, grade A*, first class honours degree - however you're scoring things this one comes out top.