When it comes to protecting your self online (if you feel unsure about the merchant) the best solution has been mentioned a few times. The virtual, temporary, or online card number is king. I set the expiration date for month and do any risky business on this card. A changing card number can be a hassle, so for large merchants I still store my normal card number (ie Amazon, utility companies, paypal, etc)
If you don't have a credit card that offers this feature then the best tools you have are judgement and reputation. Know who you do business with. It is also not a bad idea to have your card reissued once every 18-24 months. Try to do it in a month other than the one your current card expires on to further protect yourself. Every time you change your exp. date your CVV changes as well.
Keep in mind that unfortunately online is just one of the many ways fraudsters obtain information, so finding out how your card issuer handles fraud is very important. Find out if you have fraud monitoring on your card, find out if they hold you liable for any amount, and for debit cards find out if they offer provisional credit.
If you don't have a credit card that offers this feature then the best tools you have are judgement and reputation. Know who you do business with. It is also not a bad idea to have your card reissued once every 18-24 months. Try to do it in a month other than the one your current card expires on to further protect yourself. Every time you change your exp. date your CVV changes as well.
Keep in mind that unfortunately online is just one of the many ways fraudsters obtain information, so finding out how your card issuer handles fraud is very important. Find out if you have fraud monitoring on your card, find out if they hold you liable for any amount, and for debit cards find out if they offer provisional credit.
How about telling us how you personally handle your credit cards to lower risk?