The airport is 26 kilometers, or 40 minutes, from the center of Beijing.
Modes of transport (available during normal flight arrival and departure times) include:
Bus: The airport bus is available on the lower level just outside the Arrivals area. There is just one government-run airport bus shuttle. Many hotels run their own airport shuttle bus services.
Taxi: Available on the lower level just outside the Arrivals area. There is no real difference between the various taxi companies in Beijing.
When arriving at the airport, AVOID drivers who approach you in the terminal or outside the terminal as these are almost always price-gaugers, who will ask triple or more the actual price. There is a taxi line just outside the terminal. Drivers should use their meter; make sure that the driver puts down the flag, as some drivers will say they forgot and ask for a ridiculous amount of money.
The cost to midtown Beijing is normally around RMB70 depending on the type of taxi, plus RMB15 for the highway toll. There is no need to tip taxidrivers in Beijing unless they render extra assistance with bags, etc.
Many of the better hotels provide a card with the taxi's license plate when you get in a taxi at the front door. Retain this card should you have a problem with the driver, or should you leave something in the taxi. If you lose something, and don't have the number of the taxi, try either your destination or departure point as it is not unusual for taxi drivers to turn lost goods in to these places. Women are advised to sit in the back seat to avoid any possible harassment.
It's a good idea to always carry the name of your hotel and any destination in Chinese because very few drivers in Beijing speak English. You can ask the staff at the front desk of your hotel to write your destination in Chinese.