If you're coming from other cities or countries in Europe and want to get to Germany then visit the bahn.de site, at the top of the page you'll see a German flag wit (Deutschland) next to it. Click on the check mark to expose other languages. There's a US flag for English.
On the left hand side note the RAIL, HOTEL, RENTAL CAR, make sure RAIL is selected. For one way travel select "single journey".
Lets say you were taking the train from Munich to Dusseldorf. In the first box enter "munich" in the second box below that enter Dusseldorf, note if a box drops down you can select from the box, in this case "Dusseldorf City".
Cleck on the calendar to the right of the date to select your date of travel.
You can select trains by the your time of departure (Munich) or the time you want to arrive in Dusseldorf. Then click on SEARCH.
When the next page comes up you'll see what you entered at the top. Then trains are listed by date and time, also the duration of the trip. ICE means high speed train (Inter City Express) anything else is slower. Also note the "Chg" which means train changes. Often buying your train tickers in advance via the internet and printing your tickets can save you money.
If you plan on several trips or even an expensive one look into buying a Bahn card which sometimes allows for big discounts which save money and pay for the card.
Peak travel during rush hour is usually more expensive.
What is involved in going from the airport to the train terminal in Frankfurt? I will be landing in Frankfurt sometime in October, but am considering a trip to the Dusseldorf area based on the recommendations from this board. Not sure how to connect once at the airport
Frankfurt Airport has 2 Terminals, Terminal 2 and Terminal 1 which are connected via a tramway (Sky Line)which takes about 3 minutes each way. Look for signs directing you to each terminal.
Terminal 1 (The bigger of the two Terminals) has an underground walkway to the Airport train station (Not the Main Haupt Bahnhof). From that station you can get on trains that will take you to the main train station (Haupt Bahnhof) or directly to your destination.
You can also walk the bridge over to the Business center and then go down to the lower level where the train station is.
The travel center offers live personnel who will assist you with buying tickets. There are also automated ticket machines near the travel center and near the tracks.
Several people have told me the people at the travel center did not speak English. So make sure you have something on paper you can show them so they understand where you want to go. Just in case.
Many trains will go first to the main train station and then to their destination.
Remember ICE (Inter City Express) is the way to go if time is important. Cheaper trains will stop at all stations and mean 2-4 times the length of travel time.
FRA is a confusing airport at times unless you just follow the signs, but when you do that, you're in good shape.
Depending on your flight, you MAY be able to add a Deutsche Bahn segment on it as an actual flight number (I think American Airlines does this, not sure about others). Also, DB is selling advance tickets for 29 Euros these days (I think with 2 weeks advanced notice or something like that: www.bahn.de. Only catch is these aren't refundable, I think, so better add in some time in case the plane's late).
If you check the bahn.de site you'll know, it varies. This is one of the draw backs to traveling with public transportation, often bus, subways and trains stop running while the club is still open. So you have to play close attention to times, be prepared to leave on time etc. Otherwise you'll be stranded or left to expensive taxi fare. Taxi's run pretty much all the time, some trains run by the hour but some only a few stops a day. Depends again on the route, club, time of day etc.