you can try below code
Dim web As Object
web = CreateObject("InternetExplorer.Application")
web.Navigate("www.facebook.com")
web.Visible = True
Threading.Thread.Sleep(5000)
web.Document.GetElementById("loginbutton").InvokeMember("click")
it might work for you
Thanks
Gaurav Dhol
Skype: dhol.gaurav