Recently I went through the car buying experience. Here's what have happened. I did some research online to see the models and the prices of the car. Then I started with Costco's car buying program, which referred me to a dealer. Went to the dealership to test drive, and negotiated to a price that they won't sell. I walked. Went online and emailed all the dealerships in the area for a quote on the car spec I gave. One of the dealers actually emailed back with a quote below the test-driven dealer's price. Went over to pick up the car.
A few years back, it took me half a day researching and half a day visiting two dealers to get the car I wanted, at a reasonable price: I think it was in the 90% percentile cheaper in true car's range, even though I bought my car in SF bay area, which is supposedly more expensive than the average price.