You should definitely look at the World Wide Web Consortium.
These are the people who create Internet standards. If you
want your pages to stand the test of time, skip the tutorials
and go straight to their site ...
You'll find all sorts of information about HTML, some links
to *REAL* tutorials designed by the same people and information
on new technology like CSS and XML. Those last two are more
advanced so start with the section on HTML.
The W3C also has the definitive HTML validator. If your pages
don't stand up to their standards, you'll have a hard time
listing with the major Portal sites like Yahoo! and Excite.
Also, look into the information provided by Netscape and
Microsoft. They have some good references.
You might also look into these sources ...
From the creators of Mosaic:
The premier Web educators @ Yale:
You can also find oodles of information in any of the search
engines and directories. You'll have to wade through a lot of
garbage, but there is good stuff to be had.
Good luck! ~*