Why UK only? You're not likely to find anything that's country-specific. For hardware,
www.htpcnews.com is probably better than anyone, and they have users from all over the place. You'll likely find better support for software on their specific forums, depending on which apps/frontend you use. i know I have seen a lot of UK users on the Meedio, Showshifter, and GotAllMedia boards.
i have not seen any HDCP related issues yet, but I have not been looking too hard. The guys at AVS would probably know better than anyone.
Powerstrip? Unless you can find your TV in their forum database or find someone else that has done it, you're not likely to get a definite answer, and will probably just have to play with it.