Although many online sources don't allow you to save or print these books, that would be the point: if the book is there, you're more than likely going to keep coming back for access, or purchase a copy of it. Very smart marketing.
But that is a post for another day.
Here is a list of free, useful and relevant web books:
- 101 Ways to Promote your Web Site
- Speed Up your Site: Web Site Optimization
- Web Analytics an Hour a Day
- Search Engine Optimization for Dummies
- Professional Search Engine Optimization with PHP
- Ultimate Guide to Search Engine Optimization
- Web Analytics for Dummies
- SEO: Search Engine Optimization Bible
- Website Optimization
- Beginning PHP and MySQL E-Commerce
- Marketing Through Search Optimization
- Practical Web 2.0 Applications with PHP