<?xml version="1.0"?>
<bookstore> 
   <book category="cooking"> 
       <title lang="en">Everyday Italian</title> 
       <author>Giada De Laurentiis</author> 
       <year>2005</year> 
       <price>30.00</price> </book> 
   <book category="children"> 
       <title lang="en">Harry Potter</title> 
       <author>J K. Rowling</author> 
       <year>2005</year> 
       <price>29.99</price> </book> 
   <book category="web"> 
       <title lang="en">XQuery Kick Start</title> 
       <author>James McGovern</author> 
       <author>Per Bothner</author> 
       <author>Kurt Cagle</author> 
       <author>James Linn</author> 
       <author>Vaidyanathan Nagarajan</author> 
       <year>2003</year> 
       <price>49.99</price> </book> 
   <book category="web" cover="paperback"> 
       <title lang="en">Learning XML</title> 
       <author>Erik T. Ray</author> 
       <year>2003</year> 
       <price>39.95</price> </book> 
</bookstore>

'Процедура загрузки xml-файла
Sub LoadXMLFile(XMLDoc As Object, root As Object)
  Dim elem As Object
  Set XMLDoc = CreateObject("MSXML2.DOMDocument")
  XMLDoc.validateOnParse = False
  XMLDoc.Load "G:\Book2.xml"
  Set root = XMLDoc.documentElement
End Sub

'заполнение combobox
Private Sub UserForm_Initialize()
  Dim i As Integer
  Dim Element As Object
  
  LoadXMLFile XMLDoc, root
  Set Element = root.getElementsByTagName("title")
  For i = 0 To Element.Length - 1
    cmbxTitle.AddItem Element(i).Text
  Next i
  Set BookElement = root.getElementsByTagName("book")
  cmbxTitle.ListIndex = 0
End Sub

'Кнопка добавления информации
Private Sub btnAdd_Click()
  Dim XDoc As Object
  Dim NodeElement As Object
  Dim TextNode As Object
  Dim Node As Object
  Dim root As Object


  Set XDoc = CreateObject("MSXML2.DOMDocument")
  Set NodeElement = XDoc.createElement("title")
  Set TextNode = XDoc.createTextNode(edTitle.Text)
  NodeElement.appendChild TextNode
  Set root = XDoc.documentElement
  root.appendChild NodeElement
  XDoc.Save "G:\Book2.xml"
  
End Sub

  
  Set NodeElement = XMLDoc.createElement("title")
....
  

Option Explicit

Public XDoc As Object
Public Root As Object

Sub LoadXMLFile()
  Set XDoc = CreateObject("MSXML2.DOMDocument")
  XDoc.Load "D:\Book.xml"
  Set Root = XDoc.DocumentElement
End Sub
 

  Private Sub UserForm_Deactivate()
  Set XMLDoc = Nothing
End Sub