This example checks all the styles in the active document. When it finds a style that isn't built in, it displays the name of the style.
For Each sty in ActiveDocument.Styles
If sty.BuiltIn = False Then
Msgbox sty.NameLocal
End If
Next
This example checks all the caption labels that have been created in the application. When it finds a caption label that isn't built in, it displays the name of the label.
For Each lb in CaptionLabels
If lb.BuiltIn = False Then
Msgbox lb.Name
End If
Next