jay its always worth searching PPRuNe for questions like that, I found:
pay at atc college
and
NATS Pay/WP
the latter one is a huge thread all about the last pay deal that included the restructuring of the pay scales dependant on where you work, its lengthy but worth a read if you really want to get up to scratch with NATS pay.
Having not fully read them both, you can expect to start on £24k if you got to TC/Swanwick and rise to about £32k once valid.