HELP:IndexOutOfRangeException

Try
Dim GetRetailPrice As New SqlClient.SqlCommand( _
"SELECT RetailPrice FROM ProductDetails WHERE ProductName = '" & _
Me.cmbProductName.Text & "'", New SqlClient.SqlConnection( _
My.Settings.ProjectTanioConnectionString))
Dim GetRetailPriceDataSet As New DataSet()
Dim GetRetailPriceDataAdapter As New SqlClient.SqlDataAdapter(GetRetailPrice)

GetRetailPriceDataAdapter.Fill(GetRetailPriceDataSet)

Dim RetailPrice As Decimal
RetailPrice = GetRetailPriceDataSet.Tables(0).Rows(0).Item(0) '<- there is no row at position 0;
Me.txtRetailPrice.Text = RetailPrice.ToString("N") '-- IndexOutOfRangeException was
'-- unhandled by user code
Catch ex As Exception
System.Windows.Forms.MessageBox.Show(ex.Message)

End Try

the contents of 'GetRetailPriceDataSet.Tables(0).Row(0).Item(0)' seem to disappear
after i inserted a new record to the database after making the selections and
then saving. making a second selection gives me an 'IndexOutOfRangeException'
saying that 'there is no row at position 0'