You said tools section, so I think you're wanting to put an item in the
Tools dropdown of the Menu bar, not a button in a toolbar. Go into
Customize (View - Toolbars - Customize). Use the Commands tab, select a
category (Macro) and a command (custom). Drag it to "tools" on the menu
bar, and when the dropdown opens, drag it where you want it. While still in
Customize, you can right-click it to change the button face, the text, and
assign it to your macro.