Juri Pakaste has instructions on how to automatically reformat the CLHS html pages, removing those rather ugly images and generally making it look cleaner.

Once you've followed his instructions you can change the look all you want just by editing the stylesheet.

(The CLHS tarball expands into a million files that have write permissions turned off; Until you do a chmod -R u+w or something, the whole tweaking process will fail silently. Juri helped me figure this out.)