grey bars on sidebars .. category, blogroll, tag .. etc.

Hi

I'm trying to replace the grey rectangle bar for Categories/Blogroll/Meta, etc. to something else. Following this thread, I used example #3 (I do not want any icons before the sub) but don’t know how to change to the circle or something else for each main category. http://www.ambit.ireneeng.com/

Also don't know where to change Blogroll .. etc.

Thanks.