<SoapDocumentMethodAttribute("http://schemas.microsoft.com/sharepoint/soap/GetAttachmentCollection", RequestNamespace:="http://schemas.microsoft.com/sharepoint/soap/", ResponseNamespace:="http://schemas.microsoft.com/sharepoint/soap/", Use:=SoapBindingUse.Literal, ParameterStyle:=SoapParameterStyle.Wrapped)> _
Public Function GetAttachmentCollection ( _
    listName As String, _
    listItemID As String _
) As XmlNode

Dim instance As Lists
Dim listName As String
Dim listItemID As String
Dim returnValue As XmlNode

returnValue = instance.GetAttachmentCollection(listName, listItemID)

[SoapDocumentMethodAttribute("http://schemas.microsoft.com/sharepoint/soap/GetAttachmentCollection", RequestNamespace="http://schemas.microsoft.com/sharepoint/soap/", ResponseNamespace="http://schemas.microsoft.com/sharepoint/soap/", Use=SoapBindingUse.Literal, ParameterStyle=SoapParameterStyle.Wrapped)] 
public XmlNode GetAttachmentCollection (
    string listName,
    string listItemID
)

<Attachments>
   <Attachment>http://Server_Name/LISTS/List_Name/
      Attachments/Item_ID/File1_Name</Attachment>
   <Attachment>http://Server_Name/LISTS/List_Name/
      Attachments/Item_ID/File2_Name</Attachment>
   <Attachment>http://Server_Name/LISTS/List_Name/
      Attachments/Item_ID/File3_Name</Attachment>
<Attachments>

Dim listService As New Web_Reference_Folder.Lists()
listService.Credentials = System.Net.CredentialCache.DefaultCredentials

Dim ndAttach As XmlNode = 
    listService.GetAttachmentCollection("List_Name", "1")

MessageBox.Show(ndAttach.OuterXml) '

Web_Reference_Folder.Lists listService = new Web_Reference_Folder.Lists();
listService.Credentials= System.Net.CredentialCache.DefaultCredentials;

XmlNode ndAttach = 
    listService.GetAttachmentCollection("List_Name","1");

MessageBox.Show(ndAttach.OuterXml);