Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As _
    System.EventArgs) Handles Button1.Click
        Dim t As New Threading.Thread(AddressOf GetSite)
        t.Start() ' Thread starten
        t.Join() ' Warten bis zum Ende d. Threads
    End Sub
    Sub GetSite()
        Dim web As New System.Net.WebClient
        Dim bytErg() As Byte
        Dim strZeile
        bytErg = web.DownloadData("http://webseite.com")
        strZeile = System.Text.Encoding.ASCII.GetString(bytErg)
    End Sub