NATS Careers is the first and main route for you.
NATS careers
The main route outside NATS is to look at getting work as an Assistant at an Airport - try your local one whichever that may be. Try and get some work experience there or for an airline, training school or whatever. Should give you an insight.
There are other colleges as Heathrow Director said, they mostly take Students from other smaller airports round the UK to train, normally paid for by the airports though some students self sponsor (Big money really).
Academic knowledge underpins everything we do I'm afraid. So you're looking for a "cushy number" or an easy life I do suggest going for something else!!
That said, even the biggest air traffic geek will be sent to sleep by the Air Navigation Order!!
Good Luck.