Hi Dan,
Try something like:

#DEFINE EMBED_ATTACHMENT 1454

oSession = createobject("Notes.NotesSession")
oDB = oSession.GetDatabase("","Test.nsf")
oDoc = oDB.CreateDocument()

oDoc.Form = "Memo"
oDoc.SendTo = "Somebody@somewhere.com"
oRTItem = oDoc.CreateRichTextItem("Body")

oRTItem.EmbedObject(EMBED_ATTACHMENT,"","C:\Spreadsheet.XLS","DisplayName")

oDoc.Send(0)

The oSession creation will launch Notes in a visible window. The "" parameter for GetDatabase uses the current PC. If you know the Notes server name (e.g. NOTESSERVER1), plug that in.

HTH,
Larry