Why would someone want to put plain text over an image? For the search engines! They treat any text near the top of the page as far more important and far more telling when it comes to determining what a page is actually about. Therefore in struggle between search engine optimization and web design or the battle between eye appealing sites and sites that get indexed properly by the search engines, every one wants their targeted keyphrases at the top of the page in a heading tag and they want a nice image at the top of the page as well.
Once again it’s CSS and/or tables to the rescue!
Actually there’s a couple different ways. You just make the image you want to use a background image. whether you use CSS or tables you need to specify the size of the table cell or layer exactly to fit the image. Now you can place all the text you want to over it and the Search engines can read it – AND it looks good!