Cabs are available at the airport and at hotels. Cost about $30 including tip from the airport to Eagle Beach. You can also rent a car or jeep at the Queen Beatrix airport or through the hotel concierge.
Additionally there is a bus system called "Arubus." This bus is great to see the island and to travel from Oranjestad to the tourist hotels all for about $1.50. You can take bus to the far end of the island, have lunch at St Nicholas, see how the 90,000 islanders live. The bus stops at 9pm.
You can find city/island buses at a main station right downtown. During other than "rush hours", friendly drivers and some riders will help you choose routes and provide commentary on stops and sights. Fares are quite modest. An economical way to get to the resort beaches.
Because Aruba is small, consider not renting a car until you know what you want to do. Many activities are central to the resort area of the island and are within walking distance. Renting cars/jeeps is easy, and many rental companies provide pickup service from area hotels.
If you do decide to rent a car, be aware that the local rental car companies often rent older, higher mileage cars. It's especially important to recognize that even the big brand rental car agencies will rent you a vehicle in poor condition that may or may not function properly.
Driving in Aruba
The most important thing U.S. drivers need to remember is that there are no turns on red. Also, there are several roundabouts (circles), which can be frustrating to some drivers but are quickly gotten used to. Aruba uses international road signs, which generally have no words or obvious relation to their meaning. Fortunately, tourist maps usually contain quick references to these road signs if you are unfamiliar.
The major road is LG Smith Blvd, on which people usually drive at about 40 mph, though that is a very rough guideline. Because the island is so small, everything of interest is close to everything else of interest, and it takes special talent to get lost—if you don't know where you're going, you can basically just keep driving, and statistically speaking you are likely to end up where you need to go eventually. It should be noted, however, that most of the roads are not identified by signage.
The lack of road signage can be especially frustrating in downtown Oranjestad, so it might be best to park near the Renaissance Mall and simply walk to your destination. A cab might also be easier than navigating the narrow unmarked streets.
You should also be cautious when driving, as there are certain "bus only" roads that are not marked but that feature large pits in the road designed to trap normal cars while letting buses drive through.
International road signs are used in Aruba. Foreign & international driver's licenses issued by a member country of the Geneva Convention, are valid. Car speedometers and road signs are in kilometres. The speed limit in urban areas is 40km/h; out of town it's 60km/h, unless a higher or lower speed is specifically indicated. Much of Oranjestad's traffic is one-way and at intersections, where there are no road signs, traffic from your right has the right of way.
Although the island has a half decent transport system of its own, you can take life on this laid back island at a pace that suits you by using a car hire vehicle. Take a map with you to determine what road signs mean because they are not immediately obvious. This is one of the easier holiday destinations to negotiate your own car around so keep the pace easy and book ahead online.