Hello,
The Common Toolbar is home to the Insert Hyperlink button, using a chain link as the image for the button. The HTML toolbar does not have this button on its toolbar. You cannot create a custom toolbar to only display what you wish to use, but you can hide toolbars you choose not to show, as well as remove buttons from toolbars you choose not to use.
Hope this helps, if you have anymore questions, please feel free to ask.
Thanks,
-Steve