Hola, mira haber si te ayuda esto:
Cita: Public Sub SortListBox()
Dim t As New List(Of ListItem)()
Dim compare As New Comparison(Of ListItem)(AddressOf CompareListItems)
For Each lbItem As ListItem In lb1.Items
t.Add(lbItem)
Next
t.Sort(compare)
lb1.Items.Clear()
lb1.Items.AddRange(t.ToArray())
End Sub
Private Function CompareListItems(ByVal li1 As ListItem, ByVal li2 As ListItem) As Integer
Return [String].Compare(li1.Text, li2.Text)
End Function
saludos