Once you discover your wallet or credit cards are missing, immediately call the Police and file a report. If you find the items the next day, you can always cancel the report. Many people wait a day or two to, "see if it turns up."
That day or two is all a good identity thief needs to steal your identity and credit history.
You should also immediately place a fraud alert with all three national credit-reporting organizations and the Social Security Administration. Tell the organizations that your identity information has been stolen and instruct them to contact you by the telephone to authorize any new credit.
Once a thief steals your credit cards or wallet, s/he will quickly do two things: send a change of address information to your existing credit cards so you will not receive the bills showing the items they charged; and apply for new lines of credit under your name using your reputation to approve the credit line.
By the time most victims discover what has happened, the damage to their credit history has already been done. For some victims it takes months and even years to straighten out bad credit reports.
You can prevent problems before they occur by using some common sense tips:
Do business with companies you know and trust. Before you give credit card information make sure you know who is receiving it. Many Internet auction sites are just brokers for private dealers. Check the reputation of the dealer before deciding if the purchase is worth the risk.
Use a secure browser. Normally you will see an icon of a padlock near the bottom of your screen when a secure browser is being used. A secure browser limits the chance that a computer hacker can break into on your transaction and capture your account information.
Be wary of "free prizes" and other sign ups on the Internet that require personal information from you. An identity thief may use that claim to get you to divulge information needed to steal your identity.