If you only have a couple of days, then maybe fly. The Elipsos takes 13 overnight hours to make the run, and it'll cost you a minimum of 70 Euro each way for a bed in a four-person cabin.....if you book far enought in advance to get one of those discount tickets. Several discount airlines make that run, including easyjet and vueling to CDG, and easyjet to Orly (the Paris airport I prefer). Airfares each way can be as low as 30 Euro all in. Just be aware of all the policies...check-in deadlines, luggage sizes and weights, etc. If you still want to travel by train, you can book at the French rail website, tgv-europe.com up to 90 days out and get a PREM ticket for 70 Euro. These you can print out at home. On the second page, indicate you'll pick up your tickets in Great Britain (to keep the site in English), then look for the PREMs fare. You could also book it at the Spanish national rail site, at www.renfe.es . But their on-line booking system is tough to master. You can also call them to book tickets at 011-34-902-240-202. Daytime hours in Spain (GMT+2 right now...GMT+1 after October 25th) will give you a better chance of getting an English-speaking operator.