Toolbars have become a thing of the past. Very few of the modern browsers support toolbars. Internet Explorer is the only one I can name off the top of my head because of how horrifically outdated it is. According to the Google Toolbar website, Internet Explorer is in fact the only browser that the toolbar works on. Is there a particular part of the Google Toolbar that you find useful? As far as I remember (it's been a long time since I've used Google Toolbar), it's just a search bar on the browser that allows you to search Google. If there's something else that the toolbar does that you want Firefox to do, I'm almost certain there's a way to get the same functionality in Firefox.