The airport closest to Pondicherry is Chennai. Chennai is well connected to all major Indian cities. Airlines serving Chennai include Jet Airways, Spice Jet, Indigo, etc.
From the airport you can take a prepaid taxi to Pondicherry for about Rs 2000. The trip will take almost 3 hours.
You can also take a train - http://www.indianrail.gov.in/ - or a bus from Chennai to Pondicherry. Buses leave several times a day from Koyambedu Bus Terminus. Buses and trains will also take about 3 hours once you reach the train station/bus terminal.
Pondicherry is such a beautiful place and the best way to see it is on foot. It can be extremely hot between 12 and 4 (when alot of the city is quiet) but you can still cover alot of ground by walking in the morning or late afternoon. Explore the French Quarter and take a break at a cafe. There is so much to see - the colorful houses, the small details you'd only see by walking, etc.
Make sure to visit the Tamil Quarter as well. Depending on where you're staying, you may want to take a rickshaw to the area and then walk around.
Since most places you'll visit within Pondicherry are under 5-6 kms, rickshaws are the best way to go. They are plentiful and cheap. Most rides run Rs 20-30, longer distances run Rs 60. Taxis are available for longer rides.
Taxis round-trip to Auroville run Rs350, rickshaws Rs 200.
Pondicherry is small enough to get around by bicycle. There are several rental places in town. Be sure to get a lock for your bicycle.
Also availalbe to rent are motorcylces and scooters.
Most places will require proof of passport and a driver's license for any rental.
There is a toll booth just outside Chennai, and they collect about Rs. 50 for a round ticket to Pondy. After you have cross the toll booth, the experience is different.
If you drive in the night, you find that the road is dotted with reflectors on both the sides and in the middle, it looks superb. There many be many such places overseas, but, to have one world class road in India, is a great thing. People who have driven on this one, will surely agree.
On the road to Pondy, we took the East Cast Road, popularly known as ECR, stretches along, obviously the East Coast, ie Bay of Bengal, and connects all villages, towns and cities on the East Coast. It runs from Chennai to Kanyakumari, the southern most tip of this country, and is 737 kms long. If you decide to drive all along, if would be a great road trip.
If you started driving from Chennai you would have covered 113 kms, if you reached Pondy. The Road connects Chennai to Pondicherry, Cuddalore, Nagapattinam, Tuticorn and soem other small towns along the coast.
Parts of the road are scenic, with a lovely view of the sea lined with coconut trees, casuarinas trees, fishermens villages, catamarans neatly arranged along, or just plain beach sand……and nothing else. No matter what’s on the shore, the drive is great. While you drive, you will see that the sea coast on the left, it is sometimes, just a few feet away, and at some places, it is about a kilometer away, but, with nothing else in between to hide the view, the view is breathtaking.