Sarra is encouraging and helps with organization. She also has free resources if you sign up for her newsletter.
Here's a bit about NaNoWriMo.
National Novel Writing Month began in 1999 as a daunting but straightforward challenge: to write 50,000 words of a novel in thirty days. Now, each year on November 1, hundreds of thousands of people around the world begin to write, determined to end the month with 50,000 words of a brand new novel. They enter the month as elementary school teachers, mechanics, or stay-at-home parents. They leave novelists.