Difficulty Automating Javascript Web Form

Question

I want to automate filling out a javascript form on a secure website.  I apologize but am not able to give the site url, and you couldn't access it if I did.  It is a form we fill out often at work.
There is one "select" drop down box that has two options, first is blank, second is "General Reference" -default is blank and an "onchange" command then populates the form with several other elements, two text fields which also
need to be filled out.
Because the user must be signed into the website already (we are not allowed to automate logins), my code so far grabs the correct open web browser and sets it as an object shell. 
Although I can control the browser and have tested it by changing url locations, it seems as though I have no access to the document, innertext, or form elements.  I don't know what I'm doing wrong.  It's as though the IE.document is completely
blank.  But I can clearly see it under "View Source." 
Although I attempt to "getElementsByTagName" it never works, regardless of which tag name I use. 
Here is the code I have so far:
Sub testingThisWorksToGrabOpenWeb2()
Set objShell = CreateObject("Shell.Application")
IE_count = objShell.Windows.Count
For x = 0 To (IE_count - 1)
On Error Resume Next ' sometimes more web pages are counted than are open'
my_url = objShell.Windows(x).document.Location
my_title = objShell.Windows(x).document.Title
If InStr(my_title, "ARCIS") Then
Set IE = objShell.Windows(x)
Set objCollection = IE.document.getElementsByTagName("select")
MsgBox objCollection.Length
'*** No matter what tagname is used it comes back as zero'
'*** There should be 3 "select" drop down lists showing, but they don''t'
Exit For
Else
End If
Next
'here is the tag I need to change from blank to "General Reference"'
'<select name="s_2_1_43_0" onchange = ''SWESubmitForm(document.SWEForm2_0,s_7,"","1-E5BYAR")'
' style="height:24;width:140" id="s_2_1_43_0" tabindex=1997 >'
'<option value="" >'
'<option value="General Reference" >General Reference'
End Sub

Answer 1

Thank you Luna.  But the above code is VBA and I am attempting to automate a form in IE through EXCEL.  Probably should have mentioned that above though I'm pretty sure this was the right spot for this question.  Can you move it back to VBA
please?
With that said, I've solved this problem.  I had a frames issue and did not realize that.
When I right clicked on the browser and selected "View Code" it brought up the document within that particular frame that I clicked on.  I haven't worked with IE in a while and did not know the young programmers at MS had made that change to the browser. 
Doing that in the past would have brought up the top document, which defined the frames and the VBA developer could easily see that he was dealing with frames and what their names were.  This time it took me two days to figure that out.  Good idea,
just wish I had known about it.
Anyone in the future with the same problem might print out your outtertext to see exactly what it is.  In my case I discovered it was nested frames.  I was beating myself in the head tryig to figure out why I couldn't find the elements I was looking
for.  It was because my script was accessing the top frameset document.
Here is the adjusted code showing how I found the frame documents I needed.  It was double nested:
Sub getOpenBrowserAndFillFormInFrame()
' this script grabs open browser with specific url and '
' changes a drop down list item inside a nested frame '
' Then fires onchange event to repopulate form elements '
' Next step: Get names of new fields to fill out '
Dim HTMLdoc As HTMLDocument
Dim myString As String
Dim resultClasses, resultClass, resultClasses1, resultClass1
' The section below locates correct browser and assigns it '
' to object IE'
Set objShell = CreateObject("Shell.Application")
IE_count = objShell.Windows.Count
For x = 0 To (IE_count - 1)
On Error Resume Next
my_url = objShell.Windows(x).document.Location
my_title = objShell.Windows(x).document.Title
If InStr(my_title, "ARCIS") Then
Set IE = objShell.Windows(x)
Exit For
End If
Next x
' The section below sets variable to correct frame document, '
' sets variable to the correct "select" list,'
' and changes that list to show list item # 1'
Set HTMLdoc = IE.document.frames("_sweclient").document.frames("_sweview").document
Dim suffixSelect As HTMLSelectElement
Set suffixSelect = HTMLdoc.getElementsByName("s_2_1_43_0")(0)
If optionIndex >= 0 Then
suffixSelect.selectedIndex = 1
End If
' The above code changes the dropdown box but does not fire the '
' onchange event. The code below does that in order to place additional '
' text boxes and drop down lists to the form through the sites javascript '
HTMLdoc.all("s_2_1_43_0").FireEvent ("onchange")
End Sub