I would have thought there would be plenty of fell running to be had in Weardale and further North in The Cheviots. To the south you'll have the N York Moors.
Mandale AC in Stockton used to do a bit of fell racing I think. Not too sure about any other clubs in the NE. Personally when I lived there I was a member of Keswick and then Borrowdale. It was easier to get from Teeside over to Cumbria to race.
Top tip would be to join the FRA (Fell Runners Association). Its about £12 per year these days and you get a yearly calendar with all the English races plus a thrice yearly magazine (which takes a third of a year to read cos its full of interesting articles and NO adverts - RW please take note).
Plenty of shorter races with large fields where navigational skills are not really necessary. However learning to use a map and compass isn't that hard and the FRA run courses on mountain navigation.
If you've done some X country and trail races then you'll have some idea that the fitness requirements are a bit different. Its not that fell runners are any fitter per se they just, by the nature of the event, have to work on different things to the average road runner.
Hill work is important as you'd expect. However the most important thing you'll need to learn is how to descend. I know it sounds daft but fell races are won and lost on the descents - and even a midfield runner need to know how to do it. To practice descending you need to be on the fells or somewhere pretty steep with a loose surface and plenty of things to trip over. I'm a bit middle aged now - but even so I do a couple of specific downhill sessions a week. When I was more competitive I did four or more.
Trail shoes will do for the moment. When you get to do the Wasdale Horsehoe you might want to buy some proper fell shoes. However a lot of folks run in Montrails etc,.
So to summerise. Join the FRA, do some serious hill work, and pick yourself a nice out and back race (about 5 or 6 miles with 800 - 1000 ft of climb). Turn up and have a go.
Your first reaction will probably be "Never again". However after about 10 minutes you'll find yourself flicking through the handbook looking for the next race.
Have fun