Moutiers station is served by the Eurostar Ski Train direct from London St Pancras, as well as TGV services from Paris. From Moutiers it's a 25 minute drive up the hill to Meribel.
The Eurostar Ski Train leaves St Pancras on a Friday night, and arrives in Moutiers on a Saturday morning, or leaves St Pancras on a Saturday morning and arrives in Moutiers on Saturday evening. There are no sleepers on the overnight train.
The return journey can be taken all day Saturday or overnight Saturday night. Outbound night trains run from 21 December 2012 to 5 April 2013. Outbound day trains run from 22 December 2012 to 6 April 2013.
Alternatively you can take the Eurostar to Paris at your leisure, and then the overnight from Paris Gare d’Austerlitz to Moutiers on the TGV.
Contact Rail Europe on 0844 848 4078 or Eurostar on 08432 186 186 for full details.