This goes back to my previous posts about community and how you find other like minded gamers.
If your search for people who play the same games as you is starting completely from scratch then the best routes that I've found are -
Internet search for clubs - you shouldn't limit that search to the game/format that you're looking to play. Invariably a gaming club will have players of various games so be prepared to search for games that aren't on your list. e.g. searching for Warhammer and Bolton will bring up a variety of information about wargamers in Bolton. That may lead you to find Board/Card, CCG or RPG players
The other primary source of gamers is the game store. The Find Your Game Store website helps you to locate game stores throughout the UK and a lot of them will either have onsite play space where you can get to know that localised community or will have information on groups of gamers in your area who play the same games.
Manufacturer websites also in some cases have event locators. e.g. Wizards Of The Coast have a locator which enables you to search for organised play events for D&D and Magic.
If after exploring each of these and you still come up blank then I'd suggest alternative approaches -
If you have a FLGS nearby to you then offer to run demos of the games that you want to play. That way you might just be able to build that player base that you are looking for.
Check out your local University and College setups to see if they have any gaming societies or semi-related subjects for societies like Sci-Fi / Fantasy themed societies. Even if you aren't a student yourself this suggests at least that there is a population of people who would be interested in playing the games you want to play.
Plus going back a few posts I looked at the Online Communities that exist. Whilst it is possible that any post you make will be lost in the noise of the forums it'd definitely worth posting.