The below reference is a good doc on where to buy Arduino in Bangalore
You can also buy at OM Technology center in SP Road, when i went for buying there, i only got a clone of Uno as they ran out of stock. The clone costed 700.
The clone had “Freeduino USB 1.1″ printed in it and i had a tough time finding what to choose in Arduino IDE to load it. Finally by mistake i choose Arduino Uno and it gulped the code. All over the net, Freeduino USB 1.1 mapped to Diecimilia.
This is the best documentation on step by step guide on how to install CP2102 driver and get the freeduino board working
i tried in Mac 10.7 and it didnt work, then switched to my Windows 7 bx and was able to load the program.