In that case you could get a VERY good spec normal laptop for the £700-£800 mark, even £600-700 would get you a good one. I've just ordered myself a Dell Inspiron M1330 which is 13.3" widescreen and gets good reviews. It comes with and HD audio option which, with the HDMI output as standard means you could output high definition audio/video to an HD TV if you have one. It also has an LED-lit screen which helps with battery life and you can get a graphics card option for it with a Geforce 8400M GS. Anyway, it could be an option, but there are lots of other good ones out there like the new Samsung Q45:
http://www.samsung.com/uk/business/b...mobile/q45.htm
http://www.trustedreviews.com/notebo...Samsung-Q45/p1
Read some reviews of other 12" or 11" laptops and see what models they compare them to, then search for reviews on those models. You're definitely best looking at review sites like PC Pro, Trusted Reviews, etc as they really put them through their paces and are honest about their shortcomings.
Good luck!