Finding controls on FormView

I am having a problem getting the value of a field on a databound grid.

Here is the situation:
I have a Formview, that contains a Datagrid, that has a databound control.  I need to be able to get the value of that column so I can determine whether to do an insert or an update to a table.

Here is the definition of the Formview:
       <asp:FormView ID="FormView1" runat="server" DataSourceID="odsHeader" DefaultMode="Edit"
            Width="100%" DataKeyNames="SUBMITTAL_ID">

Here is the definition of the Grid:
      <rad:RadGrid ID="rgContactsDisplay" runat="server" AutoGenerateColumns="False" Skin="ABL_Std" GridLines="Both"
              DataSourceID="odsContacts" AllowMultiRowSelection="true"  Height="170px">
              <MasterTableView>
                     <Columns>
                          <rad:GridTemplateColumn UniqueName="grdCheckbox">
                                 <ItemTemplate>
                                       <asp:CheckBox ID= "chkContacts" runat="server" />
                          </rad:GridTemplateColumn>                                                                       </ItemTemplate>                                                                                                                                                                                                       
                          <rad:GridBoundColumn DataField="COMPANY_TYPE" UniqueName="company_Type" Visible="True" HeaderText="Company Type"
                                 <HeaderStyle Width="130px" />
                                        <ItemStyle Width="140px" />
                           </rad:GridBoundColumn>
                           <rad:GridBoundColumn DataField="COMPANY" HeaderText="Company" UniqueName="company" Visible="True"
                                  <HeaderStyle Width="140px" />
                                         <ItemStyle Width="140px" />
                           </rad:GridBoundColumn>
                           <rad:GridBoundColumn DataField="COMPANY_CONTACT_DATA" HeaderText="Contact" UniqueName="company_contact_data" Visible="True">
                                 <HeaderStyle Width="130px" />
                                      <ItemStyle Width="140px" />
                           </rad:GridBoundColumn>
                        <rad:GridBoundColumn DataField="CONTACTS_SOURCE" UniqueName="contacts_source" Visible="False" />
                        <rad:GridBoundColumn DataField="DOCUMENT_COMPANY_ID" UniqueName="document_company_id" Visible="False" />
          </Columns>

Here is what I have so far:
Dim grdContacts As RadGrid = CType(FormView1.FindControl("rgContactsDisplay"), RadGrid) //THIS LINE DOES GIVE ME A GRID OBJ
Dim grdSource As GridDataItem = CType(grdContacts.MasterTableView.FindControl("contacts_source"), GridDataItem)
//THIS LINE COMES UP WITH GRDSOURCE = NOTHING

What I need to be able to do is check the "contacts_source" field for a value so I can determine how to process.

Obviously I'm doing something wrong with the definition for grdSource, can anyone tell me what I need to do?

Many thanks in advance.

Rich