For car owners, the biggest expense, after the car itself, is often the insurance.

In the last 20 years, insurance rates have risen twice the rate of inflation, and they're expected to keep rising.

Consumer reporter Becky Thompson teams up with Consumer Reports with advice on how you can shop for the best deal.

The cost of insuring your car is expected to jump nearly 7 percent in the next year, so it's going to pay to shop around.

Consumer Reports does the Web surfing for us and points us to one site for with some of the best insurance quotes.

Susan Bertoldo has a clean driving record. She's never been in an accident. But like most car owners she's shocked at the high cost of insurance. And she's been frustrated finding a decent policy.

"I've been calling places, but they won't give me quotes over the phone. And they want you to come in and fill out all this paperwork," Bertoldo said.

Now she's trying the Internet to see if she has any better luck.

Consumer Reports just checked out the most popular web sites for comparing auto insurance rates. Researchers entered information on a fictitious test couple insuring two vehicles.

Most of the sites proved disappointing. For example, at Insurance.com the questionnaire took nearly half an hour to fill out. And it seemed intrusive with questions asking whether you're "married, single, or divorced without custody of your children".

And two of the sites Esurance.com and Progressive.com are owned by insurance companies.

Helen Popkin says, "Well, they'll give you quotes from several other companies, but they'll only sell you policies from their own company."

Consumer Reports found by far the most useful site is InsWeb.com. It took 14 minutes to fill out the form. And it provided instant and detailed custom quotes from several insurance companies.

For the same test couple, prices ranged from a low of $193 a month to a high of $371 a month.

So, for someone like Susan, Consumer Reports says InsWeb.com is a web site worth trying.

As part of the evaluation of auto insurance Web sites, Consumer Reports' Consumer WebWatch reviewed the sites' policies for privacy and customer service.

InsWeb earned high marks in these areas.