I have found FlipKart to be very useful when comparing prices. Here's an example. I recently got an email from one of the computer vendors in Thimphu, which contain prices of Acer laptops. I looked up these laptops on FlipKart. The specs are nearly identical. Here's a table comparing the prices on Flipkart and the local vendor's price:
|Acer Aspire AS5733||
|Acer Aspire E1-431|
If I remember correctly, there's no tax on IT equipment coming from India. Why the huge difference? Your guess is as good as mine.