Spain/Portugal/Gibraltar - Lisbon-Madrid Overnight Train

Hi all,
I'll be travelling to Portugal and Spain next Fall (September). I'd like to take the overnight train from Lisbon to Madrid. Should I just book through the Spanish National Rail site or is there someplace else I should be looking?

Also, I hear that for some Spanish trains you have to make a reservation and then reconfirm a second time? Is there any truth to this?

Thanks!

Seat61 always has good rail travel advice, and suggests a few web sites for the 'Lusitania' train: http://www.seat61.com/Portugal.htm#via%20Madrid

You can book it on renfe's website. Once you have the printed ticket you don't need to reconfirm.

I would, however, suggest flying between LIS and MAD. It only takes an hour and can be had for a lot less than the train. There are a number of LCCs on this route as well as legacy airlines: IB, TP, UX, VY, JK, and EZY come to mind.

the train is so much more fun than flying in this case. It is a very pleasant and comfortable ride although it may be more expensive than flying. The renfe site is pretty easy to use. Just follow the instructions on seat61.com

Also, I hear that for some Spanish trains you have to make a reservation and then reconfirm a second time? Is there any truth to this?

No