Finding places to play Magic the Gathering games
As for your location-specific needs, I don't know that many people can speak to that.  However, for the more generalized "How do I find more places/people to play Magic with," here are a few answers:


Wizards of the Coast has a Store and Event Locator
Check your LGSs (Local Gaming Stores) - many will either run Friday Night Magic, regular events, or casual play days
Look online for people or groups that play in your area (e.g. something like Craigslist or http://www.meetup.com in the US - not sure about the UK)
Teach other people to play


Besides those, there's always Magic the Gathering: Online - yes, it's another place to spend money on Magic (and you don't physically own the cards), but lots of the older (and less-played newer) cards can be found very cheaply, and it shouldn't be hard to put together a decent collection and play online.