Most of the time I get my hotels from otel.com, you get top class hotels for a lot less price. A lot of the time though you don't get the name of the hotel until you've actually paid, but it does tell you the location of it. We've always had great hotels.

Try http://www.imperialhotels.co.uk
I've stayed at both the Imperial and Tavistock but all of their hotels are in the Russell Square area so very central with the British Museum, Theatreland, Covent Garden and Oxford St all in walking distance.

Rooms are a bit dated but i've always had a clean room with a comfortable bed and hot shower. If you do book make sure you look at their BOGO offer, you get a 3 course meal on the first night and can eat in any of their hotel restaurants http://www.imperialhotels.co.uk/offers.aspx

thanks marcuschap - I've just this minute booked my train tickets. I was tempted to do it last night, but it went a bit late. I'm glad now as they were £40 cheaper today. I'll have a look at that website this evening.