|New iPhone 5|
1) Pre-order and ship. Pre-order the iPhone 5 without contract (starts at $649) from Apple.com and ship it to India via shipping sites like vpost, Shipitto, borderlinx, bongo etc. It should cost around 20% to 30% more for the price of the original. Currently there is a 2 week waiting for pre-order shipment processing.
2) Buy it on ebay.in or sites like shopyourworld. There are many sites like ebay india or ShopYourWorld that buy iPhones and sell them at a huge markup. The advantage here is the price is fixed so you don't have to worry too much about customs or other taxes to be paid.
3) Buy it from the grey market. Apple provides international warranty for up to a year (3 years with apple care). So don't worry too much and get your hands on an iPhone 5 by buying it from your local grey market. Places like Lamington Road, Palika Bazaar, Ritchie Street and Burma Baazar will sell them to you starting 22nd of September. Be ready to pay a huge markup on these phones.
4) Buy it via your cellular provider. Last but not the least, wait for your iPhone 5. Airtel and Aircel are said to bring the iPhone 5 sometime around diwali (November). So if you are in no hurries wait for the iPhone 5 (like me). This way you can wait for a proper nano sim to be released and also enjoy limited complimentary 4g services from Airtel and Aircel.
Do remember you need a nano sim to use the iPhone 5. Also don't forget to collect your EarPods with your new iPhone.
Note: An acquaintance of mine got his hands on an iPhone 5 from Honk Kong for $1500. You can cut your sim to a nano sim with steady hands and a bit of sand papering (they did it for him). Things work well out of the box, although some services like 3d maps, 4G LTE , High quality voice calls are currently not available in India.