If you own a website then you need to download and read this free PDF e-book titled "Beginners Guide to SEO" from seomoz.org. This 50 page guide has some great information in it. You can read it online or download it to your computer and print it out. Whether you just want to learn more about SEO or are serious about making changes to your site to increase your search engine rankings this guide will be of great use.
Seomoz is one of the leading authorities on Search Engine Optimization. They have tons of free tools and information on their website. Go and check them out.