Has anyone thought of creating a HTML template to help create CSS rules and styles?

The situation we are running into at work is this: I was given some sample content and a poorly structured design. I rebuilt the structure, created the CSS and it looked good (as good as the original design anyway).

The problem is that the content was limited in terms of the variety of structures: there were only H1, paragraphs, and unordered lists. As we build pages from the template, we are encountering more and more HTML structures that weren't present in the original sample text and we are having to go and created new CSS rules.

From a CSS coding perspective, this isn't a big deal at all. But, the issue is that the designers are having a bit of a fit because they want to be involved in the decisions for the design of different HTML structures such as H2, H3, H4, blockquote, tables, table headers, table captions, and so on.

If we had had richly structured HTML content (valid of course) in the first place, we could have dealt with these design issues early on rather than now.

Does anyone know of something like Lorem Ipsum that has a variety of HTML structures against which CSS may be applied?