Save your time—and sanity—and do most of your car shopping from home. Go online to find franchised dealers in your area. Search each dealer's new-car inventory to find out what's on hand as well as cars that have yet to arrive. This will give you an idea of what's readily available.

Sometimes you'll see on a dealer's site a "special internet price." Don't be fooled by that. Any price offered—whether online or in print—should be no higher than what they would give you if you walked in the door. But at least it gives you an idea of the scale of discounts freely offered.

Some brands, such as Honda and Toyota/Lexus, prevent their dealers from advertising any price lower than the MSRP, less available rebates. In that case, you'll have to deal with a salesperson directly to get a price.

You can go two ways here: Build a car online and submit it to the dealer/dealers, or just send them an email that specifies what you're looking for. "I need an LXE with the sports package, driver-convenience package, and a navigation system, in either black or gray but not white. It looks from your inventory that you have three on your lot. Is that the case?"

Be clear about how you want to interact—by phone or email. If the reply is positive, ask for the best price. "I'm ready to buy right now, but I'm shopping around and I want your best out-the-door price on that car."

In your electronic dealings with the dealership, set the same ground rules you would if you were there in person. You are looking for the best "out-the-door" price, including any add-on fees such as "documentation," aka "conveyance," that can't be avoided.

Make Dealers Compete

Do this with several dealers, asking for their lowest out-the-door price. Have each one email or fax you a copy of the window sticker and the vehicle invoice of the cars you're considering. The window sticker will spell out the car's features in detail, including options packages. The vehicle invoice will show you the dealer and retail costs for the car and options, and possibly incentive and holdback information.

One game dealers play is to put car descriptions on their websites that are very often designed to confuse. Dozens of standard features, such as antilock brakes and power windows, may be listed under "options," and options packages are often not identified as such. The distinctions are important, and the window sticker spells them out.

Get in Touch

Talk with the sales department—via phone or email—of the dealer(s) that quoted the best price, and establish that the car is actually there. Not just on order, and not in transit, but actually on the lot. It sometimes happens that dealers advertise a car they don't actually have, or they continue advertising a car they've already sold.

Don't Rush Out

Resist any invitation to "come down and talk about the car you're looking for" until you're good and ready. You already know what you're looking for. It's true that dealers can and do swap cars with other dealers to fill a customer's needs. So just because they don't have the one you want doesn't mean they can't get it. But there's no need to drive to a dealer to talk about a car that's not on hand.

Once you've made up your mind, call or email the dealer you would most like to work with. Explain that you've been in contact with several other dealers, you have written quotes in hand, and you'll buy the car if you can come to terms. Tell him or her you're willing to make a deposit if he or she can tell you the 17-digit VIN (vehicle identification number), provide a copy of the window sticker and/or the vehicle invoice, give you the final price, and, if the car isn't at the dealer, tell you when it will arrive. Don't get talked into making a deposit as a condition for a dealer to just start looking for an available car.

One reason this method works, especially if the car is already at the dealership, is that the salesperson and dealership have invested little time in making the sale. Before you hand over your credit card number, have the dealership email or fax you the purchase order so you can double-check that everything is correct. Be sure to check that the VIN is on the purchase order, and double-check that it matches the one on the car when you take delivery.

Of course, you can avoid the hassle altogether by using the Consumer Reports Build & Buy Car Buying Service to get competitive prices from local dealers who are held accountable for high customer satisfaction.