I was almost gonna start an SNCF layout myself! I was going to base it somewhere in the Alps, where trains had to change locos from electric to diesel. I like the Corail Lunea and Intercites trains, and I could have had 26000s, 22200s, 68000s, 72000s etc. Would have made a nice layout, but I'm happy I decided to go Irish with all the new stock coming out at the moment! Quai59 is another good website, but they don't take credit cards. Also you could try Le Petit Train Bleu, quite comprehensive