Nice and easy. :) Office 2003 I presume. Right click a blank area in the toolbar, click Customise Toolbar. This allows you to move, add, and remove toolbar buttons. :)
Sometimes though the buttons you are want ARE added, but are HIDDEN because they are sharing room with other tool bars. Use the small (Dotted) grip to the left of the Toolbars to move them arround, and make sure each toolbar as sufficent space to display all of it buttons limitlessly.