The style of the numbers and bullets provided in the Text Editing Toolbar are dependent upon the style you select. The easiest way to change your bullet and number styles is to change your entire style template.
Alternately you can change the style of your numbers and bullets by using HTML. If you are interested in giving that a try, you can add HTML by dragging and dropping an HTML widget onto your page.
The HTML Editor will open up that will allow you to write or paste in your code. When you are done, click Save and you will see the way that the HTML displays on your page
This is a link to an HTML tutorial that gave code snippets for different styles of bullets.
Please keep in mind that while the code may work now, we cannot guarantee that it will continue to work in the future. Codes can become obsolete and/or conflict with the enhancements made to provide you with the best Sitebuilder possible.