怎样用VB找到句柄并打字上去啊`

我想用vb编写一个QQ消息自动发送的程序，请问在QQ消息发送框打开后怎样找到他的句柄并把我要说的话（假设为123456）写上去并发送出去呢？
帮我写下整个代码好吗？假设QQ消息发送框在任务栏显示的名字是（与 3359652聊天中）``

以下是一个小程序的源码，点击按钮后就自动打开记事本，并在记事本上输入“hello”！QQ的以前我用
Private Declare Function SendMessage& Lib "user32" Alias "SendMessageA" (ByVal hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, lParam As Any)
Private Declare Function FindWindow Lib "user32" Alias "FindWindowA" (ByVal lpClassName As String, ByVal lpWindowName As String) As Long
Private Declare Function FindWindowEx Lib "user32" Alias "FindWindowExA" (ByVal hWnd1 As Long, ByVal hWnd2 As Long, ByVal lpsz1 As String, ByVal lpsz2 As String) As Long
Const WM_SETTEXT = &HC

Private Sub Command1_Click()
Shell "Notepad", vbNormalFocus
Dim h1 As Long
Dim h2 As Long

h1 = FindWindow(vbNullString, "无标题 - 记事本")
h2 = FindWindowEx(h1, 0&, "Edit", vbNullString)
'记事本的句柄
'MsgBox h1 & "刚刚打开的记事本的句柄"
SendMessage h2, WM_SETTEXT, 0, ByVal CStr("hello")