See the latest study on the national incidence and prevalence of stalking and harassment from the perspective of victims. This BJS study has taken on very difficult definition and measurement issues and come up with estimates for the year 2005.
Table 4 shows the numerical distribution of stalking and harassment and the gender characteristics of victims and perceived offenders. This table is percentaged in the wrong direction if you want to know the likelihood of stalking by offender gender. Of course the unit of observation is the victim and not offender, but looking at the data in another way can give us insight into stalking.
Repercentaging the table for cases in which there was a known gender of offender (n=3,033,434), we find that approximately 17.8% of the (2,060,779) male offenders stalked male victims and approximately 82.2% stalked female victims. In contrast, only about 38.8% of (972,655) female offenders stalked males and about 61.2% of female offenders stalked females. Thus, both males and females are more likely to stalk females than they are to stalk males.