Transports in Turkey
Turkey is an enormous country with a lot to see. This means you need a good transport network to go around. Most commonly used are the planes: a lot of cities have airports (even international ones) and to fly is very common to fly around (also cheap).
For those who don’t like planes (like me!!) or who want to go to a place where there’s no airport, you have the buses.
Turkish Airlines: the main provider of international connections from and to Turkey. If you are arriving from an international destination to Istanbul you will land on Ataturk Airport (European side) and if you are going on a domestic flight the airport will vary. Sometimes, the prices of domestic flights can be as cheap or cheaper than Pegasus or going by bus.
Pegasus is the Turkish low cost. They flight domestic and international and have really competitive prices compared to Turkish Airlines. On the downside, you have to pay for luggage and food, but if you are on a budget, it’s great. They always land on Sabiha Gokcen when in Istanbul.
List of all the airports in Turkey http://en.wikipedia.org/wiki/List_of_airports_in_Turkey
Buses form Turkey’s most widespread and popular means of transport. The network is extensive, buses are well kept and comfortable, and you’ll be offered snacks and tea along the journey.
Pamukkale Turizm (Aegan coast), Metro Turizm, Kamil koç, Ulusoy, Varan: most of them (or even all) have website where you can buy tickets from. Be sure you know where their office and departure places are. Sometimes language can be a barrier, but they probably speak basic English.
Renting a Car
I would recommend renting a car if you are planning to explore areas around Cappadocia and places without much traffic in general. You have to be a bit crazy to rent a car in Istanbul, for example. There are almost no traffic rules and even though locals can deal with it, it’s going to be a lot harder for you to do it.
Car rental agency: http://www.citytransferistanbul.com/rent-a-car-istanbul.html?lang=en