The basic creation code looks like this:

HWND CreateList (HWND hWndParent, RECT rcl)
{
   HWND hL;

   hL = CreateWindowEx (WS_EX_CLIENTEDGE,
                        "LISTBOX",
                        "",
                        WS_VISIBLE | WS_CHILD | 
                        WS_BORDER | WS_TABSTOP,
                        rcl.left, rcl.top,
                        rcl.right - rcl.left, rcl.bottom - rcl.top,
                        hWndParent,
                        (HMENU) NULL,
                        hInstance,
                        NULL);
   return (hL);
}

You can use the same code to create a tree, simply by substituting WC_TREEVIEW 
where it says "LISTBOX" above. The RECT is in client coordinates for the parent 
window.

Incidentally, if you're doing this for a dialog, here's a neat way of doing 
it maintainably. You create an (invisible) frame in the dialog (called 
IDC_LIST_FRAME here), convert the coords of that from screen to client, and 
pass that as the rect into the above function. That way, if you need the 
listbox resizing, you can do it at design time without any tedious faffing 
about with coordinate trial and error :

void OnDrawTheDamnThing(HWND hDlg) 
{
   RECT rScreen ;
   RECT rClient ;
   HWND hFrame ;
   POINT pTL;
   POINT pBR;

   hFrame = GetDlgItem (hDlg, IDC_LIST_FRAME);

   if (hFrame)
   {
      GetWindowRect (hFrame, &rScreen);

      pTL.x = rScreen.left;
      pTL.y = rScreen.top;
      pBR.x = rScreen.right;
      pBR.y = rScreen.bottom;

      ScreenToClient (hDlg, &pTL);
      ScreenToClient (hDlg, &pBR);

      rClient.left = pTL.x;
      rClient.top = pTL.y;
      rClient.right = pBR.x;
      rClient.bottom = pBR.y;

      CreateList (hDlg, rClient);
   }
   else
      OutputDebugString ("ERROR - Can't access list frame");
}

For those of you using MFC, consider replacing the POINT tomfoolery above 
with calls to the overloaded CWnd::ScreenToClient which takes a RECT.