This is actually an idea that's been in the works for many years and could have a number of different uses. Besides the possibility of tourism, some of the more important/beneficial uses are to bring supplies and resources up to the ISS or future projects such as a 'shipyard' where we can build the ship for the first manned Mars mission, or further exploration. The main reason being, at a shipyard in orbit we could build a much bigger ship that provides more space for it's inhabitants and supplies, and not have to worry about launching from the earth into orbit which requires huge amounts of fuel. Right now, the space shuttle is launched into space on top of a huge fuel tank (and 2 smaller ones attached to that) with rockets on it's bottom, and then all those tanks and rockets are just dropped back to earth and the shuttle does it's thing. If launching a ship that is built in space already, we wouldn't need all that extra fuel or fuel tanks and rockets, to get it up there. We also wouldn't need to worry so much about aerodynamics and heat shielding, so the ship that is used to take our astronauts to wherever they're going can more easily be designed for artificial gravity and space recreation and laboratories and storing equipment. When the astronauts return, they can more easily and safely dock at the space station or dock, and ride the elevator back down with any samples they bring back. Then, inspecting the ship, and refueling for it's next flight is much easier and safer.
If you've seen the movies 2001 or 2010, or even the more recent movie Mission to Mars, those are how I would expect our ships to look if they're launched after already being built in space.
The space elevator is a great idea that I'm hoping we have the technology to begin work on in my lifetime.
P.S.- To expand on Royale stating that it was in Star Trek Voyager episode, it was an episode that Nelix 'saved the day' because he had an idea how to fix the elevator thanks to having done work with them in the past.
I bet you will love it! 
