Violet H.
Yelp
Update November 2016: I am pleased to report I had no problems this year accessing the JR West wifi.
Original review: Initially, this place can be a bit confusing, but once you figure out a few things, it's a great place. First, let me explain the building a bit. The station is accessible; there are elevators by the stairwells. The front part of the station is open to anyone, regardless of whether they have a train ticket or not. For ease of understanding I call it the common area. There are stores and restaurants here, such as the Japanese version of 7-11 ("Seven Eleven Heart In"), a Lotteria (burgers etc.), a curry place, and more. There are two JR offices here, one close to the East entrance, and one close to the West entrance. Here you can trade in your vouchers for your JR Pass and make reservations on the Shinkansen by talking to a human being. Look for a green sign that is supposed to be a person reclining in a seat. It can be easy to miss the first time, which I did, and walked too far. You can also buy tickets from machines right outside the offices.
Once you have a ticket - whether for the subway (Midosuji Line only) or the Shinkasen or the train to Kansai Airport - you can enter into the train station. If you have a subway ticket, you run it through the machine to get in. If you have a JR pass, you show it to the staff member at the opening right next to the machines. (JR passes do not go through the machines.) The Midosuji Line goes to Osaka Station, which opens up many other subway options, including the Loop.
On this level there are coffee and souvenir shops, and food stands. There are nice large restrooms with Western style toilets. Lots of places to sit and wait, and no one hassles you, even if you are there for awhile. Although Osaka claims to have lots of WiFi, I always had trouble with it. When I first came I had to go to Drip X cafe and buy a beverage so I could get their WiFi code and email my host at the place I was staying at.
If you are taking the Shinkansen, you must go through a separate Shinkansen gate (on this floor), where you will have to show your pass and ticket. There are additional food and other booths here, and seating, on this concourse. I had a nice beef sandwich here from one of the stands one day. From here you will need to take the stairs or elevator to get to the tracks. Look up first and find your gate number before going up, so you end up in the right place. Otherwise you will have to come back down and then go back up. There are some seats (not a whole lot) and some small food stands with snacks. The Shinkansen is on time - not early, not late - unless something terrible happens, which is rare, so you can wait downstairs where there are more seats and more temperature control. Just make sure you know where you are going and leave enough time to get upstairs, based on your level of mobility. Electronic signs show the different routes and track numbers. Mostly they are in Japanese but they do run in English, too. I rode mostly on the Hikari Shinkansen and I easily learned what it looked like in Japanese.
Subway lines are downstairs. Your train will also be downstairs if you arrive from/are going to Kansai Airport. There are enclosed waiting rooms downstairs.
To get out, you have to go down if you took the Shinkansen or go up if you took the subway/came from Kansai Airport. Coming from the Shinkansen, you go back out the gate through which you entered. Then you exit the train station (again through the gate) into the common area that anyone can use. Only then do you finally exit the station itself. (This sure confused me the first time.) From the subway or Kansai Airport, go upstairs on the escalator or elevator, exit the train station into the common area, then exit the station completely through the appropriate gate. In all cases it's best to know which exit to take that is closest to your eventual destination. Exits to the outside, which are called gates, may have directional names ("East Gate") or other names like "Sakurabashi Gate" or be named after subway lines ("Midosuji Gate").
It is helpful that Japanese numbers are the same as English. As with most other places the staff at a shop will calculate the amount of your purchase on a calculator and then write it down on a piece of paper for you. Except for a couple of coins, the money is clearly marked and easy to use. When paying, put the money in the tray provided.
Unlike some stations, Shin-Osaka does not have any department stores located therein. You can pick up a bus, taxi, or rent a bike. There's a stop for a bus that goes to Osaka (Itami) Airport.
For the most part, Japanese people are very courteous. . .except in train stations. If you are slow or in their way they will not hesitate to crowd you or cut in front of you. I did not enjoy this but I was forgiving because they've got to get where they're going and no one was horrendously rude.