"If you are having trouble making up your mind, many dealers will let you take the car home overnight if you ask."
Ideally, you could complete the entire car buying process online. However, there is no substitute for getting out on the road and doing a test drive. At some point, you'll want to get into a few cars and see how they feel. This can be a daunting task knowing that you will have to face a pushy salesman. You'll need to be prepared to get in and get out with only what you need: an evaluation of the car, not a strong-arm sales pitch. No one likes having to reject others, but you're not ready to start negotiating yet, so follow these steps to make this a quick and painless process.
Example: "I'm trying to decide between the [Honda CR-V] and the [Toyota RAV-4] and would like to test drive each one today. I have a lot to fit in and I'd like to try to get over to the [Toyota] dealership by [3pm]."
They will also certainly ask if you are ready to buy today. Let them know you are serious, but remind them you have plans to test drive several vehicles from different dealers and you'd like to do a comparison first. Before you leave, you'll be happy to get their business card so they can get the sales commission should you decide to buy from their dealership.
Example: "I'm planning to make a decision within one week, but I need to try out a few different vehicles first. After the test drive, you can give me your contact information so I can make sure you get the commission if I decide to buy a [Honda CR-V].."
Example: "I don't want to waste your time negotiating today since I'm still evaluating several models. If you want to give me a price quote that would be fine, but I am not ready to make my decision until I take a few more test drives."
Lastly, if you already know what you want and prefer to start out by negotiating prices online and then test driving later, the Internet salesmen will be happy to let you come by for a test drive.
Once you decide what kind of car you want you can...