You can edit tcl/toolbar.tcl and put a # at the start of a line if you want to remove a button.
You can add your own buttons in there too - e.g.:
Code:
toolbar_add_button " TCE... " "menu_uveditor" "Start
AC3D's Texture Coordinate Editor (UV Mapper)"
Buttons can also be added via a script (rather than editing AC3D main code).