(Only for SharePoint 2007 as SharePoint 2010 does not have bullets in Quick Launch!)
Sometimes it’s the little things…
I had a request where a site owner wanted to change just the bullet used in Quick Launch. They did not want to create a custom theme or do a complete rebranding of the entire site, just change the bullet.
Create your new bullet image in your favorite paint program (JPG or GIF format) and upload it to a library in your site, or if you have server access to the Images folder in Layouts.
Use SharePoint Designer to edit the master page and add the CSS below just after these two lines:
Or, if you want to do a quick test, instead of editing the master page add a Content Editor Web Part (CEWP), edit the CEWP, click the Source Editor button and paste the following.
The result (with a horrible bullet image!)
Hopefully you are a better artist than I am!
If you just want to hide the bullet then set background-image to none: