Back to main workshop page
The HTML primer that I learned off of long, long ago was The NSCA Primer. I still think that it's good.
The W3C is brings us good things, web-wise. Bookmark this site. Also, you might want to bookmark the HTML 4.01 Specifications and the CSS 2 Specifications.
Also useful are the HTML Validator and the CSS Validator.
There is also a nice list of character entities availible.
Which brings me to O'Reilly's vast, vast collection of books that might be useful.
There is a lot more there on just web design/programming alone. Not to mention the plethora of books on Perl, which has plenty of web-oriented uses.