Privacy Policies.
Many companies will prominently post their privacy policies, where they state that they don’t share your information with others. If a company Web site does not make mention of this kind of secure online shopping, avoid providing them with your personal information. There’s no guarantee that a company with a privacy policy will honor it, but you stand a better shot of safeguarding your info with one that claims to.

Online Promotions.
Dozens of surveys, promotions, contests and opinion polls ask you to sign up online at any given point, but think twice about distributing your personal information to such businesses. Most of these are set up primarily to retrieve your contact information. To avoid having your information in the hands of companies you don’t even know, resist the urge to complete the forms.

Security Measures.
Look for symbols on the Web site that ensure security for your payment information. While they are never 100 percent secure, a strong payment security system makes it extremely difficult for hackers to access your financial information, such as credit card numbers and bank accounts. Consider using a payment service, such as PayPal, where you transfer money into the online payment service from your bank account. The online retailer gets only your PayPal information, not the bank info.

E-Mail Addresses.
Avoid making it easy for spammers to get your e-mail address. Clever programs scour the Web searching for valid e-mail addresses, so don’t put your actual e-mail address in your e-mail signature. Also, change the address just enough when posting on a forum or message board so that it’s easy for readers to e-mail you, but the harvesting programs will be confused.

Online Communities.
With message boards, community profiles and personal pages such as MySpace and Facebook, you can reveal as much or as little about yourself as you want. Err on the side of caution and keep relevant and identifying information private. Avoid listing such seemingly innocent information such as your phone number, address, school or work name, hobbies and even the names of family members.