Just wondering...about ID's

[Amon Ra]

I have a handle

HWND hbtnGetHandle; //get the handle

and this to create a button:

 	hbtnGetHandle = CreateWindowEx(NULL,"BUTTON","Get Handle",
		WS_CHILD | WS_VISIBLE, 7, 7, 90, 20, hwnd,
		NULL, g_hInst, NULL);

How do I set it so that in the wndproc, i can use a switch case
and use ID_SOMETHING? Is it in LOWORD(wParam)? if so, how do i set the id to the wParam of the button?