http://www.snowcarbon.co.uk/ski-resorts has a journey planner to a number of ski resorts in the alps and various associated information such as transfers to resort. A report in the Times drew my attention to this and stated that it is now possible to reach Swiss resorts in a day from Paddington. It also says that it is soon to introduce a "taxi share" feature to put travellers in touch when arriving on the same train. I have not tried this myself yet, but I hope that the information is useful for others.
John Russell