Não sei se compreendi bem o seu problema, mas veja se isto ajuda.
Option Explicit
Private Declare Function WaitForSingleObject Lib "kernel32" _
(ByVal hHandle As Long, ByVal dwMilliseconds As Long) As Long
Private Declare Function CloseHandle Lib "kernel32" _
(ByVal hObject As Long) As Long
Private Declare Function OpenProcess Lib "kernel32" _
(ByVal dwDesiredAccess As Long, ByVal bInheritHandle As Long, _
ByVal dwProcessId As Long) As Long
Private Const INFINITE = -1&
Private Const SYNCHRONIZE = &H100000
Private Sub Command1_Click()
Dim iTask As Long, ret As Long, pHandle As Long
iTask = Shell("Notepad.exe", vbNormalFocus)
pHandle = OpenProcess(SYNCHRONIZE, False, iTask)
ret = WaitForSingleObject(pHandle, INFINITE)
ret = CloseHandle(pHandle)
MsgBox "Ok"
End Sub