By simbel I think you mean symbol, as in icon.
Right click the toolbar and look for Customize or something similar, then choose the buttons/icons to display on it...
If something is wrong with the toolbar then reinstall it!
If you have Yahoo, just reinstall your Yahoo toolbar
http://us.toolbar.yahoo.com/
Choose your browser, and windows type, then download
If you have gmail from google , then reinstall the Google toolbar:
http://www.google.com/intl/ro/toolbar/ff/index.html
Choose your browser, and windows type, then download
If you have something else , get it yourself!