Dynamic Content with DOM2
This is a great article to get started with DOM2 ( aka: Document Object Model Level 2). It explains why the 'document.write()' property is bad and should be avoided. It takes the concepts behind the technology and breaks them down into understandable chunks. THis article does pre-suppose a basic understanding of the document object model and parent/child node relationships.
There is also
second part to this article!
http://developer.apple.com/internet/webcontent/dom2i.html