The css file linked to is in the cache - otherwise the browser couldn't read it either, there are some things you can't work around. It's one of the main benefits for using css, the file gets stored locally and all the browser has to do is download the now much lighter html code for the next page. If someone really wants it, they can take it easily. Any page you have a linked css file for, post the url, we can post the contents for it here
For instance, does this look familiar?
Edit: Can't post copyright material here. Removed JC's Stylesheet. - JoshPet