[Gem Single]

Примерно так:

HWND tray, notf, tool;
tray = FindWindow("Shell_TrayWnd", NULL);
notf = FindWindowEx(tray, NULL, "TrayNotifyWnd", NULL);
// Windows XP: notf = FindWindowEx(notf, NULL, "SysPager", NULL);
tool = FindWindowEx(notf, NULL, "ToolbarWindow32", NULL);