How to get elements that have no ID in VBScript

internet-explorervbscript

I am trying to write a script to drive my IExplorer. It works okay up to a point but then I need to enter a value in a textarea and click a button while they both have no ID. I have no idea how I can move arround in the HTML DOM using VBScript but it was suggested somewhere to use document.all somehow. I was also thinking of maybe using a JS script to give them IDs and then go back and use document.getElementbyid but I don't know how to run a JS script from within the VBScript with the initialised document object in mind. What I have so far is:

Option Explicit
With CreateObject("InternetExplorer.Application")
  .Visible = True
  .Navigate "https://adwords.google.co.uk/um/Logout"
  Do While .Busy
WScript.Sleep 100
  Loop
  .Document.getElementByID("Email").Value = "testtestingtton@gmail.com"
  .Document.getElementByID("Passwd").Value = "PWD"
  'Note: You could just get the form and submit it, but
  'you'll miss out on any special JavaScript associated 
  'with the Submit button.
  .Document.getElementByID("signIn").Click
  Do While .Busy
    WScript.Sleep 100
  Loop
      .Navigate "https://adwords.google.co.uk/o/Targeting/Explorer?"
        Do While .Busy
    WScript.Sleep 100
  Loop
'here begins the problem'
  .Document.All.tags("sB5 sPEB").Value = "southpark"
  '.Document.getElementsByTagName("sJ1").Click'

End With

Also since the field I am trying to fill is

<textarea style="overflow-y: hidden; height: 36px;" class="sB5 sPEB"></textarea>

and it has no value attribute how is its value inputed?