Delorie Software --http://www.delorie.com/web
Provides a number of free services to the web community to assist web authors who wish to make their information available to the largest audience. These tools provide alternate ways of viewing your pages, so that you can ensure that your content is received properly by all viewers.
HTML Home Page --http://www.w3.org/MarkUp
This is W3C's home page for HTML. Here you will find pointers to our specifications for HTML, guidelines on how to use HTML to the best effect, and pointers to related work at W3C.
The HTML Writers Guild --http://www.hwg.org
The Guild is the world's largest international organization of Web designers. Membership is open to anyone with an interest in web authoring and a desire to improve his or her skills.