Declare Function ShellExecute Lib "shell32.dll" _
  Alias "ShellExecuteA" _
  (ByVal hwnd As Long, ByVal lpOperation As String, _
  ByVal lpFile As String, ByVal lpParameters As String, _
  ByVal lpDirectory As String, ByVal nShowCmd As Long) As Long

Public Sub RunBrowser(lngHWnd As Long, strURL As String, iWindowStyle As Integer)
  Dim lSuccess As Long

  lSuccess = ShellExecute(lngHWnd, "Open", _
          strURL,  0 &,  0 &, iWindowStyle)
End Sub

Call RunBrowser(frmMain.hwnd, "http://www.sql.ru", SW_SHOWDEFAULT)