I'm not exactly sure what you are trying to do, but I think it is probably closer to:
<script type='text/javascript'>
$(function() {
$('#bandName').change(function() {
var x = $(this).find('option:selected').text() +" "+ $("#vID").find('option:selected').text() + " " + $('#specialGuest').val();
$('#keywords').val(x);
});
$('#vID').change(function() {
var x = $("#bandName").find('option:selected').text() + " " + $(this).find('option:selected').text() + " " + $('#specialGuest').val();
$('#keywords').val(x);
});
$("#specialGuest").blur(function() {
var x = $("#bandName").find('option:selected').text() + " " + $("#vID").find('option:selected').text() + " " + $('#specialGuest').val();
$('#keywords').val(x);
});
});
</script>
Maybe tell me what you are trying to do in plain English so I can understand what the code should be doing. I see you are trying to do something with the specialGuest text field, but I can't tell what you want it happen when the value changes.