Check if GridView Contains a value

I have a DataGridView that contains a few columns of data.
Is there a way to check a column for a value before i add a new row, just to make sure i dont put dupes in it?

try this:

vb Code:

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
    Dim found = From row As DataGridViewRow In DataGridView1.Rows.Cast(Of DataGridViewRow)() _
                Where row.Cells(1).Value.ToString = "value to find" _
                Select True
    MsgBox(found.FirstOrDefault)
End Sub

This is how I search value in a datagridview:

For i = 0 To DataGridView1.RowCount - 1
If DataGridView1.Rows(i).Cells("Column1").Value = "Value" Then
MsgBox("x")
End If
Next