+1

Do your research before you even think about going to the dealership. Check out Autotrader and look at what private sellers have to offer and what dealerships have on their lots. That will give you a good idea of where you can expect to start as far as price goes. From there just sit down and come up with a price you are willing to pay for that car.

When you know what you want and what you are willing to pay it gives you more confidence for dealing with the salesmen. Make them agree to your price and make sure it is an "out the door" price without any added dealer fees or taxes on the back side. Don't let them talk you into looking at something else or upgrading/downgrading if you have already decided what you want.

As has already been said, don't be afraid to walk away. When I bought my Vette I told the salesman and the used car manager what I would pay for the car. They told me they couldn't do it so I said I was going to look at a few more cars in the area and they could call me if they changed their mind. They called back 4 days later and we ended up at an even lower price than I originally offered.