Phoenix is by far the largest city in Arizona and due to its rapid growth it's racing its way up the list of top 10 largest cities in America. That growth has come with the price of endless sprawl in every direction, but for the visitor Phoenix never feels out of control. The location in the middle of the desert shapes nearly everything about the city. From Christmas through May the dry heat and sun make Phoenix arguably the nicest and most consistent climate in the entire country and this attracts millions of visitors each winter and spring. During the summer the temperatures can stay in the triple digits for over 12 hours each day, which can be exhilarating for a few days, but eventually wears nearly everyone down.
What To Do
Most people come to Phoenix not to see the sights, but to enjoy the perfect winter and spring weather. As a result the two most popular activities for the visitor are playing golf and sitting around the hotel pool. Hey, there's nothing wrong with either of those things once in a while! It's impossible to drive more than a couple of miles in Phoenix without passing a golf course and this continues well out into the suburbs. The area has many top ranked courses and prices tend to reflect that. There are a few public courses that are cheap, but it's hard to get a tee time unless you call a week in advance.
Scottsdale is the upscale city attached to Phoenix's northeastern edge and the only way you know you've crossed into it is things suddenly get a bit nicer. Scottsdale has a really lovely, if a bit touristy, old town section where you can stroll around through an old western town and shop for souvenirs and high-end clothes. It's also loaded with restaurants, bars, and nightclubs so it's a great place to spend your evening. Downtown Phoenix itself has rebounded in recent years and there are a lot of interesting and new nightlife options there, but it's not a great place to stay unless you are in town on business.
You are going to want to fly into Phoenix's Sky Harbor Airport. It's large and a major hub of several airlines so it's possible to get good deals all year round. There is no train service into Phoenix, but there are Greyhound Buses, although they aren't a popular mode unless you happen to be afraid to fly since with a bit of notice flights can be almost as cheap.
If you need to go to the airport by car you can save both money and time if you pay for your in advance. You can also choose a Phoenix airport shuttle which can be quite convenient considering there isn't much public transport available in the area.
Where To Stay
If you are coming to Phoenix to golf or sit by the pool you'll find hotels and resorts all over the area. The ones in Scottsdale tend to be nicest and most expensive, but places in nearby Tempe and in Phoenix itself can be quite reasonable. There are no hostels in Phoenix at the moment, but this isn't really a hostel kind of town anyway.