When I went there last September, we missed our connection flight in London, leaving us with either 1) Renting a car 2) Train or 3) Bus.
Since I was the only one with a license, and had only had it for a few months, I really didn't fancy driving all the way up to Newcastle on the wrong side of the road. Trains were fuck off expensive, leaving us with the bus option. Worked out well enough for us, had a few lagers at a pub just by the bus station, and then managed to sleep almost all the way up. Hardly ideal, but it's probably what I'd recommend.