Have a look through the forums using the search bar at the top, there are plenty of places all over the UK to explore, find a place on the forums you'd like to explore, then do a bit of Google research, pretty easy to find locations, just got to spend some time and do a bit of research :)
Meets are usually advertised on the forum well in advance. Unfortunately you've just missed most of the summer ones. Best thing to do is get a couple of reports up from any old derp to show that you actually explore. Once you've done that its a lot more likely that people will invite you along.
it'd also help if we knew what sort of stuff you're into. I'd offer to take you somewhere but you're about 3 hours from me and I generally only do underground stuff which tends to put a lot of people off.