In the past (more than 5 years ago) I was able to successfully book and print tickets, as well as look up schedules for planning - on their SNCF Voyages.com website. I remember it was a little tricky to get to English language (I'm in U.S.) site, but I managed. I don't want to be switched over to Rail Europe, which is what they do. Does anyone know how to do this?

I'm planning a Spring trip to Paris and will have 15 days. I've been to Paris many times, so don't need to stay there the whole time, so I'm researching various options for a few days in the middle of the 2 weeks to spend somewhere else. At this point Bruges interests me the most, as I've never been (I love all things Medieval). Maybe a side trip to Ghent, too. Anyway, I need to look up train options, prices, etc. and the SNCF site is frustrating. I know enough French to get an idea, but would be uncomfortable buying the tickets that way, with all the "flexibility" options, etc. I used to love PREM tickets, but not anymore, too much can happen.

Also, how far in advance can you book? 3 months? I know that it's less expensive the further out - and tickets to Belgium don't look cheap!

Any help would be appreciated.

Use this one: https://www.trainline.eu

Help here: http://www.seat61.com/France-trains.htm

Apparently much has changed since you used the French rail system, including the link you posted, which no longer works (for me, anyhow.) Try this instead: http://en.voyages-sncf.com/en/
The bump to RailEurope, which always could be avoided with some effort, now is a simple matter of choice. The home site is smarter, quicker, more user-friendly. For further advice, check out the master of rail travel, www.seat61.com which can steer you to the sites for Belgian inter-city travel.
It remains true that booking three months/90 days gives the best prices. But some major routes are announced earlier than that, plus some trains have special cars that are cheap and quiet. You can also sign up to have SNCF promotions sent to your e-mail.

Use Trainline - it's the same as SNCF, with the same schedules and the same prices. Or use the English SNCF site (without being transferred to Rail Europe).

You can use www.captaintrain.com and get the same prices. I'm not sure if they have all of the tickets that SNCF does or not, it seems at least once there was one kind I couldn't get on their site (a shorter run) that I could on SNCF, but I might be remembering wrong, give it a try.

For a couple years I had trouble with my American credit card on www.voyages-sncf.com no matter what, so that's why I used capitaintrain. But last summer I could again use it okay on the real SNCF website as I recall.

I only use www.voyages-sncf.com in French so can't help you on that one. I don't think it switches you to Raileurope based on language, just based on where you claim you live. In fact, the button where you change languages lists countries, not languages. Just click on "Europe-other countries" at the bottom right to get what you want, I believe.

captaintrain sends you to Trainline now, they changed names, actually.

I bought Paris-Strasbourg PREM tickets at www.trainline.eu for next month trip. Very easy purchase using a U.S. credit card without fuss. With most of the tickets purchased from trainline, I got 6 digit retrieval codes. I have collected actual tickets at SNCF machines using those codes plus my last name several times now. But other times, the site gave me the PDF version of bar coded ticket.

Be careful with cheap tickets if flexibility is important to you. They often can't be changed.

Great information, thanks so much everyone. I'm sure I can find my info on one of these sites.

We will be looking at some train travel next year. Great links for my notes.

If you can be flexible when you travel, oftentimes the fares will be much lower during off-peak hours and during certain weekdays.

And Belgium is independent from france so look at Sncb.com which doesn't exist anymore - something like Belgianrail.
Don't bother to book in advance in Belgium - only fast train cheaper in advance is the Thalys running from Paris to Bruxelles to Amsterdam.
If you are above 60 you benefit from the senior rate - nearly free - courtesy of my taxes.

Does the senior rate apply to non-EU seniors? Is any special documentation or card needed?

The senior rate applies to everyone. If you buy tickets online and print them out, you choose your age category. No one checks on it IME, though I suppose a conductor could see when you hand him your ticket that you've gotten the senior rate, and question it.

If you ride French trains often, you can get a free Voyageur card and accumulate mileage for future discounts. You don't need to be an EU citizen for that, either.

The www.trainline.eu site is great. Looks very easy to book and gives you all the options, including Thalys or SNCF. Senior rates help, as train tickets are rather expensive these days, and for seniors the tickets are exchangeable and reimbursable - great. Being a senior does have a few compensations! Just wish I could do this train travel sans suitcase. If so, I would take the Paris/Lille/Ghent/Bruges option on SNCF (which is cheaper than Thalys) and spend a few hours in Ghent. Oh, well ....

Regarding a visit to Ghent, it says on this site that there are luggage lockers in Ghent, 2 stations:
https://visit.gent.be/en/luggage-sto...ontext=tourist

I don't think it has anything to do wiht being a senior fare as to the exchangeable and reimbursable conditions, it has to do with what fare you buy. With any kind of ticket (senior or not), there are about 3 choices of tickets, and if you buy the most expensive where you can exchange them or get a rebate, the conditions are the same for seniors or others. Same for other fares. The cheapest fares are not reimbursable for anyone, senior or not. I'm not sure where you read that seniors get special rights regarding refunds.

In fact, they often don't even have senior fares on some of the ticket types, such as the ones that are modifiable. They will list a rate if you put in your age as 60+ but it's the same rate as other ages for some trains and times of day. It doesn't make the nearly free, it may only take 10 euro off the ticket price on a route such as Paris to Bruges (ie, going from 70 euro to 60 euro) and for some of the more popular times, it may not discount the fare at all for seniors. Even if you have the annual SNCF Senior Carte, it doesn't give you special privileges about refunds.

Buying a reduced fare isn't going to get you much in terms of ability to get a refund or exchange as the refund conditions generally relate to time periods before departure, not after, if the idea is you can get that if you miss your train, if you buy a reduced fare ticket.

Of course you have to have documentation to prove your age, you have to have ID to travel in Europe anyway (presumably your passport). Sure, they may not ask for it, but you shouldn't travel around without some official ID anyway.

I looked into the Senior card - when you do the math, unless you travel frequently and on a pretty regular basis, it won't make much of a difference in price. I don't think this is designed for Seniors who just take one or two trips per year.

The best advice is to purchase 3 months in advance and/or when tickets go on seasonal special.