One book that has helped me get on with my projects has nothing to do with game development (or does it?)
It's http://www.amazon.com/On-Writing-Memoir-The-Craft-ebook/dp/B000FC0SIMOn Writing A Memoir of the Craft by Stephen King.
It's a lot about writing stories and his journey as an author, but also about putting your tools together and thinking creatively. A lot of what applies to finishing good novels also applies to creating well... anything. Especially for the lone indie developer.