Actually, it's sort of like buying fish at the market, with the difference that the haggling is usually done over the phone.
The way I did it was to get quotes from different banks and pit them against each other and finally take the lowest one. Took a little time and effort, but well worth it for the money saved (I paid only 18500 in interest for a 4lakh loan spread over 2 years). Putting that money in a simple bank FD would have fetched me more than twice that interest.