Huatulco International Airport (HUX) is only a 15-20 minute drive from the resort areas, making for an easy experience coming and going. The facilities at the diminutive airport are modern and comfortable. The lack of flights to Huatulco from the US and Canada has been a sore point among local business owners, and at this moment there are still very few options to choose from. Domestic flights are increasing with the addition of budget Mexican carriers like Interjet from Toluca. Rumors have it that Interjet will open service to Los Angeles and maybe San Francisco, but this remains to be seen.
Continental flies daily nonstops from Houston to Huatulco from Dec-April, or at least they did in 07-08. In the summer they fly Wednesday and Saturday, and during the spring and fall off-season they fly Saturday only. With US-based carriers making dramatic cutbacks due to skyrocketing fuel prices this year, the future of Continental's scheduling is unknown.
Mexicana has 3 flights daily to Huatulco via Mexico City, from airports throughout the US and Canada. American Airlines does codeshare flights with them, and many other airlines service Mexico City as well. If you have to make a connection through the anarchy that is Mexico City Airport, make sure to read Tips.
Charter flights operate to Huatulco on Saturdays from Denver throughout the winter on Frontier Airlines, and from Chicago on USA3000 Airlines. SkyService is the Canadian charter outfit that flies to Huatulco. Canadian travel agents offer package deals with airfare and a week's lodging at the huge all-inclusives Gala or Barcelo for less than just the hotel rates at the resorts would usually cost. The same is true of American travel agents like Vista World Travel that specialize in Huatulco. Information on these deals can prove elusive to find on the Web, so the best bet is consulting a travel agent about what's available. The charters are specifically designed with packages in mind, so if you're not booking a hotel package, you would probably be better off booking on one of the major airlines.
Rental cars are available at the airport from Thrifty, Advantage, Hertz, and Europcar. Make a reservation online and the prices can be shockingly cheap, as little as $130/week.
Just as it is at most airports of the world, taxi service from the airport is a racket - the taxi concession that has exclusive rights charges $45. (That's for the whole car. Don't let them try to charge you $45 per person.) Taxi service to the airport, on the other hand, is only around $10 from any cab in town. Once you're in town, taxi service is surprisingly cheap to get you on short trips around town. Anywhere in La Crucecita, and between La Crucecita and Santa Cruz or Chahue, is 20 pesos ($2.00). (It was only 16 pesos until recently, but just went up.) Between La Crucecita and Tangolunda is 40 pesos. For more extended trips, the prices get a lot more expensive.

For those coming or going around Mexico by bus, the very modern bus station is on the north side of La Crucecita on the main road into town. Buses leave here for just about anywhere you can think of in southern Mexico.
Though Huatulco is located near the bottom of Mexico, the country curves so much to the east that it's not much longer a drive from Texas than Cabo San Lucas is from California. Part-time residents and intrepid explorers will welcome my detailed information on border crossing and driving here via the Gulf route (Brownsville - Tampico - Veracruz - Acayucan - Salina Cruz - Huatulco). With considerable improvements to the nation's highways in the past ten years, and the advantage that there is no torturous mountain driving on this route, it has become a very reasonable trip to make. Click on the icon for a downloadable PDF document that will guide you through it.