There are thousands of great books and audio's out there that you can listen too. I love turning my car into a driving university and listen to audio's that help me gain different perspectives on life.
The top success books I've read are:
1. The Magic of Thinking Big
2. Think and Grow Rich
3. The Secret
4. How to Win Friends and Influence People
5. Millionaire Fast-lane
6. Rich Dad Poor Dad
7. The law of Success
8. 21 Irrefutable laws of leadership
9. Your Wish is your Command
Personal development is key to both your mind and life success. It is dependent on your life and where your mind is at. This is why it's called personal, so you have to pick a book/audio that will speak to you.