When you a thinking about a website design, you may not have your content ready to go.  In fact this is so common that there is a ready answer to this problem.

Most professional web designers use Lorem Ipsum text.  Here is a site that will tell you all about it, and generate as much as you want–for free.  http://www.lipsum.com/

Here is another Lorem Ipsum generator with a different, but useful approach:
http://html-ipsum.com/