You need to take advantage of human nature. If you walk in, or ring them and ask the price, they will ask for the moon. Go for a demonstration and ask lots of questions, let the salesman work. The more time you spend, the more he will be invested in the sale. Make no mention of the price until you are ready to leave. You say "I would like to buy the model, new in the box. Take your name card (have some made with your mobile number if you are without) and write your price on the back, and ask him to take it to management for approval. If they shake their head "no" start to leave. If a reasonable offer does not come very quickly, say "you have my number, call me when you are ready to sell." Tell them you will be looking at other sellers. Then leave. Most of the time you will have a call before you get your ride out of the car park.
A word about the ST30. It is a great choice, I own a 55". It is the value priced plasma in the 3D range. The panel is the same as other more expensive model. It has also been replaced by a new model as of the CES (Consumer Electronics Show, Las Vegas) in January. In India, it should come with a 3 year warranty card (don't lose it) a single pair of glasses and possibly a WiFi USB antenna. (The WiFi depends on distributor whims)
Being it is an old model now, dealers will be trying to flog their demo units on you. Don't accept delivery until you check the usage meter for how many hours and power cycles the TV has experienced.
Good luck on your hunt.
