checkbox in asp.net <asp:checkbox id="callback" runat="server" />

I have need a checkbox in asp.net vb, i have this so far:

in the body: <asp:checkbox id="callback" runat="server" />

but how to i work it out at the top, this is what i have for the other text boxes, but for some reason i can not get the checkbox one to work can someone help pelase!!!!!

  cmd.CommandText = "INSERT INTO members (title, first_name, last_name, company_name, house_number_name, street, address1, address2, town, postcode, telephone, fax, email, pass, web_address, sector, no_employees, hear_about_us, callback) VALUES ('" & title.Value  & "', '" & first_name.Value  & "', '" & last_name.Value  & "', '" & company_name.Value  & "', '" & house_number_name.Value  & "', '" & street.Value  & "', '" & address1.Value  & "', '" & address2.Value  & "', '" & town.Value  & "', '" & postcode.Value  & "', '" & telephone.Value  & "', '" & fax.Value  & "', '" & email.Value  & "', '" & pass.Value  & "', '" & web_address.Value  & "', '" & sector.Value  & "', '" & no_employees.Value  & "', '" & hear_about_us.Value  & "', '" & callback.Value  & "')"