I've been searching for years for an integrated UK public transport travel planner - and I just found one at
http://www.internet.xephos.com/site/xephos/en/home.phpEnter in a journey (from and to) and it looks up a combination of train and bus times for you ... plenty of other options available to specify time, date, preferance for train v coach, etc.
How good / complete is the data? How practical are the routes? It looks pretty good to me at first glance.
Some background ... until 2001, a "National Bus Timetable" was published by the Isle of Wight bus company (Southern Vectis), with sponsorships. It was really for the travel trade, and when it died it carried on as a CD based system that travel agents could buy - not cheap. They have now realised that there are members of the public who would like direct access. It's clearly using the same databases - they talk of 13000 timetables with 8 million journeys, and their reference numbers are the same as the 2001 book. The times ARE current though.
One slight downer. When you register, you get a free trail account, 1 week, 100 enquiries. You can then subscribe for 200 enquiries per month, for 2 pounds. This is probably a resource that Lisa an I will subscribe to for our business - on Friday, we were working out the return of customers to Bristol Airport, Colchester and London ...