You'll find most LCD's will support HD (1024x1024, and progressive by default), however, you really need to ensure they're HDCP compliant. This is the copy protection that will be used for premium channels. Sky will be using this in 2006 when they begin broadcasting.
An excellent place for more info on what's what is avforums.com
This is their HiDef forum, and there's a sticky right at the top that covers HD ready TV's.
http://www.avforums.com/forums/forumdisplay.php?f=104 Don't know anyone I can recommend you talking to in Northampton, but PJ HiFi in Guildford are excellent for impartial advice. (Speak to Elliot, the installs director) or Convergent AV who set up my system, speak to Gordon for the best information on the subject full stop!
http://www.pjhifi.co.uk/pj/index.html http://www.convergent-av.co.uk/ Or a quick fix, reviews section
http://www.homecinemachoice.com/ Personally, I'd go for Pioneer or Panasonic, and steer well clear of Sony. Further down the budget scales, Hitachi & Samsung, then LG.
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