Perhaps start with an existing statute and just make it a felony: For instance, here is Florida's
Statutes & Constitution :View Statutes : Online Sunshine
(d) “Cyberstalk” means to engage in a course of conduct to communicate, or to cause to be communicated, words, images, or language by or through the use of electronic mail or electronic communication, directed at a specific person, causing substantial emotional distress to that person and serving no legitimate purpose.
(2) A person who willfully, maliciously, and repeatedly follows, harasses, or cyberstalks another person commits the offense of stalking, a misdemeanor of the first degree, punishable as provided in s. 775.082 or s. 775.083.
(3) A person who willfully, maliciously, and repeatedly follows, harasses, or cyberstalks another person and makes a credible threat to that person commits the offense of aggravated stalking, a felony of the third degree, punishable as provided in s. 775.082, s. 775.083, or s. 775.084.