DateTime を使う。

d.Date.ToString のように文字列に変換して切り出せばどうにでも。

Module Module1

    Sub Main()

        Dim d As DateTime

        d = DateTime.Now
        System.Console.WriteLine(d.Date)              '=> 2009/07/28 0:00:00
        System.Console.WriteLine(d.Date.GetType)      '=> System.DateTime
        System.Console.WriteLine(d.Year)              '=> 2009
        System.Console.WriteLine(d.Year.GetType)      '=> System.Int32
        System.Console.WriteLine(d.Month)             '=> 7
        System.Console.WriteLine(d.Month.GetType)     '=> System.Int32
        System.Console.WriteLine(d.TimeOfDay)         '=> 10:18:04.3573005
        System.Console.WriteLine(d.TimeOfDay.GetType) '=> System.TimeSpan

    End Sub

End Module