Good on the basis of information provided and user feedbacks on the websites in some cases.Mouser and Element 14 are MNCs having presence in India. Bhasha Technologies are affiliated to freeduino.org,as can be seen on their homepage.Remaining are listed by arduino.cc and some I searched on google. I dont have any ads on my blog,so I wasn't advertising.
The List here -
Bhasha Technologies
Location

une
Shipping Charges: Rs 11 (all over India)
*Listed by freeduino website
Probots Techno Solutions
Location:Bangalore
Shipping Charges: Rs 75 to 115
* Listed by arduino website
Extreme Electronics
Location:Jamshedpur,Jharkhand
Shipping Charges: Rs 70
Kits N Spares
Location: Delhi
Shipping Charges: Rs 150
Embedded Market
Location

une
Shipping Charges: Rs 117
* nice interface
* Good Mircocontroller Range
* Competitive Price
Ventor Technlogies
Location:Kolkata
Shipping Charges: Rs 60
* Very cheap for small components
RhydoLabz
Location:Cochin,Kerela
Shipping Charges: Rs 72
* Listed by arduino website
MG SuperLabs
Location:Nagpur,Maharashtra
Shipping Charges: Rs 100 to 150
* Listed by arduino website
Simple Labs
Location:Chennai
Shipping Charges: Rs 150
* Listed by arduino website
Explore Labs
Location:Jodhpur,Rajasthan
Shipping Charges: Rs 50 (All India Flat rate)
* Listed by arduino website
Sumeet Instruments
Location:Kolkata
Shipping Charges: Rs 100
* Listed by arduino website
Proto Central
Location:Bangalore
Shipping Charges: Rs 100
(free shiping above Rs 1500 order)
* Listed by arduino website
Tenet Technetronics
Location:Bangalore
Shipping Charges: Rs 150 + 2 % VAT
*.Listed by arduino website
Robo Kits
Location:Ahmedabad,Gujarat
Shipping Charges: Rs 125
Element 14 (Formely Farnell)
Location:Bangalore
Shipping Charges: Rs 200
* Pan card required
* International Range
* Data sheet for all products if applicable
Mouser Electronics
Location:Bangalore
Shipping Charges: Rs 2160 (40 $)
* International Range