Public Transportation  from Delhi Indira Gandhi Airport to your destination:  (You can rent a car from 'carzonrent' (tel. 91 11 41841212 or toll-free 1860-500-1212); or take a taxi (Easy Cabs, tel. 43434343, at International & Domestic Arrivals, and Meru Cabs, tel. 44224422, at Domestic Arrivals) - counters for booking are inside the Arrivals halls). 

By Train:  (
Each of the Delhi Metro stations have their own parking spaces).
  - The passenger complex is connected via a dedicated Delhi Metro Railway Line encompassing the whole of New Delhi. Trains run presently every 12 minutes.  While the first train serves daily, starting at Delhi Station at 4:45am; the second train starts at 5:27am & the last train at 11:30pm (second & Last trains service is Mon-Sat only).  NOTE: The  Delhi etro train cut its fare in half (now Rs 10).
Dwarka Sector 21 departures to Gandhi Airport are at 4:45am, 5:15am & 11:15pm. 

  -  The New Airport Express Train* at Terminal 3, served by high-speed rail link to city center, makes currently six stops at  New Delhi (the metro station is adjacent to Ajmeri Gate side of the ND Railway station), Shivaji stadium, Dhaula Kuan, Delhi Aerocity, Indira Gandhi  Airport (IGI), & Dwarka sector 21. Trains run every 10 minutes at up to 105 km/ph and take 20 minutes. Tokens can be purchased for single, return, maximum fare, 30, 45 or 60 T Pass - or the Fare Store Value Card.
* Passengers on Airport Express
line wishing to board the Delhi Metro train from New Delhi Metro station may now purchase tokens & smart cards at the Airport Metro Station for onward travel to the New Delhi station of the Yellow Line to other Metro Lines.  (The Yellow Line operates from HUDA City Center in Gurgaon to Jaangirpuri in north Delhi.
To view the Delhi Urban Rail expansion plan map open map https://www.google.com/maps/d/viewer?mid=zUj1ihMbzw_0.kbI-AtW--zMg&hl=en&ie=UTF8&msa=0&z=10.
 -  The Shatabdi Express trains departs New Delhi railway station starting 4:45am, with increased frequency during rush hours - every ten minutes 30 seconds & at non-rush hours every 15 minutes.

By Bus: 
- Air-conditioned GPS-equipped buses start from ISBT Kashmere Gate, ISBT Anand Vihar, Noida & Rohini, make multiple stops at the first few kilometers, and then speed up to the Airport. 
- Started October 2015 - buses to Mudrika, Narela & the Airport Express have launched free WiFi service on a trial basis.

Google Plus One