If you've been scammed, there are several ways you can file a complaint:

The National Consumer League's Fraud Center. This organization can help if you've encountered telemarketing or Internet fraud. It provides information on how to prevent scams and can help you file a complaint with the appropriate government agency. You can get information on the Fraud Center's website at www.fraud.org.

The Federal Trade Commission (FTC). You can file a fraud complaint with the FTC (go to www.ftc.gov, click on "Consumer Protection" and "File a Complaint.") Complaints help the FTC track scams nationwide. If the FTC receives many complaints regarding one bad actor, it might take action. The FTC website also has information on how to protect yourself from scams.

State Consumer Protection Agency. Your state or local consumer protection agency may be able to help if you've been scammed. To find your local agency, see Nolo's article State Consumer Protection Offices.

State Prosecutor. Contact your local prosecution office and find out if it investigates consumer fraud complaints.

Local newspaper, radio, or television stations. Many local media outlets are looking for scams and fraud stories. They may have a cadre of volunteers to pursue consumer complaints.

Keep in mind, however, that filing a complaint does not always mean you'll get action or results. You may have to file a lawsuit in small claims court (if the amount in question is small) or consult with an attorney. (To learn more about small claims court, see Nolo's Small Claims Court area).

You don't owe any money if you receive an item you never ordered -- it's considered a gift. If you get bills or collection letters from a seller who sent you something you never ordered, write to the seller stating your intention to treat the item as a gift. If the bills continue, insist that the seller send you proof of your order. If this doesn't stop the bills, notify the state consumer protection agency in the state where the merchant is located. You can also complain about mail fraud to your local U.S. Attorney's office and the local postal inspector.

If you sent for something in response to an advertisement claiming a free gift or trial period, but are now being billed, be sure to read the fine print of the ad. It may say something about charging shipping and handling, or worse, you may have inadvertently joined a club or subscribed to a magazine. Write the seller to:

• offer to return the merchandise
• cancel any club membership or magazine subscription you don't want
• ask the seller to take your name off any mailing list, and
• state that you believe the ad was misleading.

If charges show up on your credit card statement, call and then write the credit card issuer. Tell it that:

• you do not authorize any further charges for the club or magazine
• you have cancelled the membership or subscription, and
• the ad was misleading and you did not knowingly join or subscribe.

Send the letter to the address specified by the card issuer for disputed charges (most likely on your monthly billing statement).

Federal and state laws prohibit unfair or deceptive trade acts or practices. If you think you've been cheated, immediately let the appropriate government offices know. These agencies often have the resources to go after unscrupulous merchants. Law enforcement in the consumer fraud area is poor in some parts of the country, but many hardworking investigators do their jobs superbly. The more agencies you notify, the more likely someone will take notice of your complaint and act on it.

To find the consumer protection office in your state, county or city, visit the federal consumer action website (of the Federal Citizen Information Center) at http://consumeraction.gov/ (click on "Where to File a Complaint" and "State Offices").

Unfortunately, government agencies are rarely able to get your money back. However, some large metropolitan areas sponsor mediation programs that help resolve problems between consumers and businesses. If the business has a license (a contractor, for example), try calling the state agency that licenses it to see if they can help resolve the dispute. Also, a local Better Business Bureau (BBB) may be able to mediate your dispute with the business. (To find your local BB office, visit the BBB website at www.bbb.org.)

Another way to get relief is to bring a lawsuit against the seller in small claims court. This may not be feasible unless the seller is local. If you plan to sue, first send a demand letter explaining the problem and asking for your money back. Many states require such a letter before you sue. For more information on writing a letter, read Nolo's article Demand Letters: The Basics. For more information about suing in small claims court, visit Nolo's Small Claims Court area. For a legal primer that shows you how to build your case, present evidence, and what to expect in small claims court, see Everybody's Guide to Small Claims Court, by Ralph Warner (Nolo).