I assume you have ListBoxSelectionMode set, and you want to loop through the selected rows in teh grid, and display the display some values from the DataSource. If so, here is code to try:
Dim cm As CurrencyManager = CType(Me.BindingContext(Me.gridDataBoundGrid1.DataSource), CurrencyManager)
Dim dr As DataRowView
Dim range As GridRangeInfo
For Each range In Me.gridDataBoundGrid1.Selections.GetSelectedRows(True, False)
Dim row As Integer
For row = range.Top To range.Bottom
Dim pos As Integer = Me.gridDataBoundGrid1.Binder.RowIndexToPosition(row)
dr =CType( cm.List(pos), DataRowView)
Console.WriteLine(dr("Column"))
Next row
Next range