SearchFileInDirTree - Searches a file on a directory tree

<System.Runtime.InteropServices.DllImport("imagehlp.dll")> Shared Function _
    SearchTreeForFile(ByVal rootPath As String, ByVal inputPathName As String, _
    ByVal outputPathBuffer As System.Text.StringBuilder) As Boolean
End Function

' Returns the complete path+name of the filename or a null string if the
' filename hasn't been found. Only the first occurrence of the file is returned.
'
' Example: Debug.WriteLine(SearchFileInDirTree("d:\codearchitects\codebox",
'  "codebox.exe"))

Function SearchFileInDirTree(ByVal rootDir As String, ByVal fileName As String) _
    As String
    Dim buffer As New System.Text.StringBuilder(260)
    SearchTreeForFile(rootDir, fileName, buffer)
    Return buffer.ToString()
End Function