Best SEO books available on the market today.
And another four SEO books which I recommend:
Search Engine Optimization: Do It Yourself – The Definitive Do It Yourself Guide to SEO
The Art of SEO: Mastering Search Engine Optimization (Theory in Practice)
SEO Made Simple (Second Edition): Strategies For Dominating The World’s Largest Search Engine
Ranking Number One: 50 Essential SEO Tips To Boost Your Search Engine Results
This is not actually a tip, but I strongly advise to have couple of SEO books, just to keep a record of your advance and mastering SEO. When you can say to yourself – I know everything in this books and I can write better one! – Then you are ready for the BIG MONEY!