This should do it from here:
Manipulating Buttons in Internet Explorer's Address Bar[
^]
BOOL FindAddressBar(
HWND mainWnd, HWND* addressBarWnd, HWND* cmdTargetWnd)
{
mainWnd = ::FindWindowEx( mainWnd, NULL, TEXT( "WorkerW" ), NULL );
mainWnd = ::FindWindowEx( mainWnd, NULL, TEXT( "ReBarWindow32" ), NULL );
*cmdTargetWnd = ::FindWindowEx
mainWnd, NULL, TEXT( "Address Band Root" ), NULL );
if( *cmdTargetWnd )
*addressBarWnd = ::FindWindowEx(
*cmdTargetWnd, NULL, TEXT( "ToolbarWindow32" ), L"Page Control" );
return cmdTargetWnd != NULL;
}