I was thinking of going to Amboise from Paris and back the same day. The French site sncf.com won't let me put a return day of the same day?
Should I just do the request seperate rather thtn putting on return? I was going to take a tour of the loire Valley?
Yes, check timetables and fares each way separately.
How are you planning to get around during the day after you arrive in Amboise?
I was thinking of takin an all day tour the the Chateau's by ACCO-DISPO Tours
from either Tours or Amboise.
I understand without a car that would be the best way to see the area?
We took an Acco-Dispo tour several years ago and loved it. Can't say enough good things about it. I'm not sure about Amboise, but I know that both regular trains and TGV trains go to Tours. If your budget can afford it, take the TGV. It's half the time. And I know that, at least for the TGV, Tours is the end of the line, making it that much easier.
Amboise is a great town to use as a base for exploring the Loire, but if you visit as a daytrip from Paris, use Tours as your gateway. The rail connections from Paris are more direct.