WiredSafety, an online safety group, says it monitors about 1,600 harassment complaints a month -- twice the number of five years ago, reported the New York Daily News Sunday.
"In real life, you have to worry about someone spotting you if you stalk them," said Parry Aftab, founder of WiredSafety. "Online no one's going to punch you in the face."
The most common forms of cyberstalking are e-mails or instant messages, but some have created a Web site to discredit a person.
In addition, penalties for cyberstalking are little more than a slap on the wrist, according to Aftab.
"You can get law enforcement involved," she said. "But most of the time, the person will just lose their account with their Internet server or whomever."