Public Structure TestStructure
    Implements IComparable(Of TestStructure)
 
    Dim Veh_Number As String
    Dim Veh_Name As String
    Dim Veh_Group As String
    Dim Veh_Sub As String
 
    Public Function CompareTo(ByVal other As TestStructure) As Integer _
        Implements System.IComparable(Of TestStructure).CompareTo
        If Veh_Name = other.Veh_Name Then Return 0
        If Veh_Name > other.Veh_Name Then Return 1
        Return -1
    End Function
End Structure

Dim lst As New List(Of TestStructure)
'Liste füllen, dann ...    
lst.Sort()
 
Dim index As Integer = lst.BinarySearch(New TestStructure With {.Veh_Name = _
  "gesuchter Name"})
if index < 0 then msgbox "Nichts gefunden"