Totally not tested but you might want to "validate" the email using the InStr function:
Code:
Dim myOutlook As Outlook.Application
Dim myItems As ContactItem
Dim msgBody As String
Dim i As Integer
dim sCompany as string
'set your variable from your form or recordset
sCompany=Me.Company
Set myOutlook = CreateObject("Outlook.Application")
Set myItems = myOutlook.CreateItem(olContactItem)
With myItems
For i = 1 To myItems.Email1Address
If InStr(myItems.EmailAddress,sCompany)>0 then msgBody = msgBody & myItems.Email1Address
Next i
MsgBox (msgBody)
End With
Cheers,
Vlad