There's not a complete list as it will vary from site to site depending on what plugins they have, but if you download and take a look at the krystle theme, you will find a css file called blockheaders.css. This contains quite a lot of the common blocks and is used to add an icon alongside the block headers.
You could use that as a starting point, changing the css rules in there to modify the colours rather than the icons, and then use a tool such as firebug to identify the class names for any other blocks you may have installed on your site.
Richard
