FINDING A GOOD deal on an auto insurance policy isn't easy these days, especially if you live in a high-cost state like New Jersey, New York or California. So when looking for coverage, be prepared to do some research. In some states, more than 200 companies write auto policies, so even if you get a half-dozen quotes, you're only scratching the surface. (In others, you'll have less than 50 to choose from.) And even once you find a company with great rates, there's no guarantee you'll get them. After all, you may not qualify for a simple reason, like a poor driving record. Worse yet, you may find that the great rate evaporates once your policy comes up for renewal in six months or a year.

So be on your guard. To lock in the cheapest deal, you may have to insure with a company you've never heard of and switch providers fairly often. Either way, it pays to shop around. Here's a guide to the most efficient way to find a good deal.

Internet Quotes
The Web is a great place to start your search. You can get quotes both from the Web sites of insurers like Geico Direct and General Electric's Electric Insurance and from services like InsWeb.

The 800 Guys
As you start collecting quotes, don't miss the insurance companies that sell their policies over an 800 number like Geico Direct (800-861-8380), Amica (800-242-6422), American Express (800-535-2001), USAA (800-531-8100) or 21st Century (800-443-3100). After all, these companies don't have to shell out 15% commissions to field agents. And it stands to reason that they'd pass their savings on to their policyholders.

Trouble is, these insurers are very picky. If you aren't a better-than-average insurance risk, you may be better off taking your business elsewhere. For instance, if even a single blemish mars your driving record over the past three years, Amica most likely won't offer you a policy unless you live in a state such as New Hampshire, where auto insurers are required by law to take all comers. (You'll notice that Amica rarely has the cheapest policy available from the 800-number carriers. But, as a mutually owned insurer, Amica pays dividends in most states, which can make the final cost of the policy roughly comparable to one from Geico.) USAA offers policies only to U.S. military families.

State Farm and Allstate
These two companies command 19.3% and 10.1% of the auto-insurance market, respectively. Like the 800-number carriers, they have their own in-house, or "captive" sales forces, but they differ from the 800-number carriers in that they operate out of local offices and offer insurance to a broad range of drivers, from the safest to some of the riskiest. For a "good risk" driver, the 800-guys will usually be cheaper. But provided your record is reasonable, you're still likely to get a pretty good deal here.

If you've had two or three accidents or three or more speeding tickets over the past three years, your best bet is to get a quote from Allstate or State Farm and then ask an independent agent to try to beat it. Most agents regularly work with six or seven companies and sometimes can cajole one of them into beating the quote. You can find the telephone numbers of independent agents in you local yellow pages under "insurance agencies."

Agency Writers
Many companies sell their insurance through independent agents. They range from giants like St Paul Travelers and The Hartford to tiny mutual companies with names like A. Central Insurance Co. These insurers pay substantial commissions to the independent agents.

But an independent agent can be a wealth of information on deals in your market, and if you have a troubled record, an agent can sometimes be the best way to find coverage at a reasonable rate.

Some examples: You can be the right sort of risk -- a nonsmoker in your 40s with a clean driving record, two cars and a home you own -- and lose out because you share that home with a teenager. "Most companies won't refuse to add a teenager to the parents' policy," says Ron Sundermann, an independent agent in Cedar Rapids, Iowa. "But to get out of the business, some companies will simply quadruple the rates for teens if they're the principal user of the car." An agent who knows the market can help find a better deal.

If you live in a rural area, you're probably better off with a local company. "Mass-market companies are not comfortable with the 'unknowns' of a rural area," explains Rick Blank, an independent agent at Preferred Services Group in White Plains, N.Y. "It's hard to get a company like that to say yes to you. There are little mutual companies in an area that have good prices, and they understand the market, which isn't as attractive to a mass marketer."

Last Resorts
If your driving record is a disaster, if you've never had auto insurance before, or if you're male, single and under 25, you'll be an untouchable to most insurers. Sure, they'll write you a policy. That'll be $5,000 please. Fortunately, there are several companies set up exclusively to handle substandard risks. And if all else fails, you can usually sign up with your state's assigned risk plan (check with your state's department of insurance for numbers).

In all such cases you'll pay much more than you would with a clean record. But you can work your way to a better rate in as little as three years. You just need to clean up your act.

Here are some of the biggest writers of substandard policies:

Allstate Indemnity, Northbrook, Ill. (800-255-7828)
This branch of Allstate is one of the nation's largest sellers of substandard policies. Allstate charges substandard customers more, but it offers them the same claims service preferred customers get.

State Farm Fire and Casualty, Bloomington, Ill. (Local number in Yellow Pages).
The largest auto-insurer overall, State Farm also runs a busy high-risk market division. Like Allstate, it offers substandard customers its full range of services.

Progressive Insurance, Mayfield Village, Ohio (800-288-6776).
Long known as the leader in issuing substandard policies, Progressive has recently been concentrating on branching out to the regular market. Always a good place to call if you're hard to insure.

Viking Insurance, Madison, Wis. (800-334-0090).
Previously known as OrionAuto, Viking Insurance offers coverage in 27 states (mostly excluding the northeast). It specializes in insuring drivers with "inconsistent payment histories" as well as those with "multiple tickets." So if you've had your fair share of encounters with the fuzz, it might be worth giving Viking Insurance a call. This is also one of the few companies out there that offers month-to-month policies, although you can expect to pay roughly 10% more for the convenience. If you already have insurance and are in the market for a new provider, be sure to ask about rollover discounts. In some states, Viking Insurance offers discounts of 10% to 15% for policy transfers.