I'm being stalked and I've had enough.
Does it relate to events in the past with that person?
Yeah, I had a creepy ex-boyfriend, he has stalked me for over a year.
You should not be made to feel unsafe. If someone is stalking you report it to the police and develop a routine and pattern where you are always protected and safe.
Stalking is not illegal. What law can I report him to be arrested?
It depends on the extent of stalking,   If he is making threats or harassing you document it.  Even if the police dont do anything, they have it on record that you brought it up.   Keep everything they do documented and let family and friends know.