a cab from airport to your hotel might be between 18 to 20 dollars one way.also across the street of the airport you can see the different car rental companies.
the one who has best prices right now is economy car rental you can check with them they are also at the airport
We have rented from Optima and Value with good results.
Probably Tropic rental enjoys the best reputation with the various bb members http://www.tropiccarrent-aruba.com/ He will meet you with the car at the airport so you don't have to schlepp your bags across to one of the little rental huts.
Thanks Arubalisa for the taxi fares list - very helpful in deciding whether or not to get a rental car. There are sooo many places we want to see a taxi would cost us a small fortune, better to put that money into a rental car.