HELP I'M BEING TaRGETED?

[Jere]

Okay so on the week before school ended, someone with the email address 'frendnumber@yahoo.com' kept sending me threat emails telling me they're going to kill me. At first I thought it was just spam and deleted it, and the following day I got 14 emails from the same address saying this: (copied/pasted)
"Hi. No need to reply <3 I'm going to kill you soon =) I hope you taste good baby. This isn't a joke, this isn't spam.. forward this email to 10 of your friends or I will kill and rape you, pretty boy."
the emails sent kept increasing more and more until like some week or so later I had 110 of the same messages!! So I deleted my yahoo and made another one, then anonymous accounts on youtube kept sending me the same messages through my youtube account. I blocked and reported them all and youtube helped me out. I figured they knew my youtube because I have the same name as in my old email address, but then this person by the name "FrendNumbah" on facebook tried to add me and send more threat messages, when I don't even have the same name! So I replied and told this person to leave me alone or I'm calling the cops and they stopped. Everything went back to normal until July. Then at that time, I started getting anonymous calls from unavailable numbers and when I first answered, this female voice told me she was 'frendnumber' and knew where I live and has been watching me sleep WTF! So I called the cops and they told me not to worry they were going to track her down, but they never found a trace or clue of her and had my phone company change my number, she stopped calling me but then started sending MAIL LETTERS with fake stamps and fake addresses with the same threat messages as the calls, along with screwed up pictures of cut-up penises and a note that said: 'do you like them? i want yours next'.
I called the cops again and since then they've been securing my house and keeping close watch, but all of a sudden this morning there were no police cars or men keeping watch outside, and my parents' alarms have been cut to pieces (Idk how).. and I'm alone in the house right now. I just got a call from that person and she told me if I called the cops or left the house I'll die! I'm in a closet right now and am using my laptop to write this question please someone help me I can't access my facebook or any of my accounts they've been hacked someone HELP WHAT DO I DO
I CANT CALL THEM SHE SAID IF I CALLED SHE'D SHOOT ME FROM OUTSIDE AND THE PHONE IS IN THE LIVING ROOM I COULDNT GET IT BECAUSE SHE MIGHT THINK IM GOING TO CALL THE COPS IN THE CLOSET!

HOW DO I CONTACT THEM THROUGH LAPTOP???? WHATS THE SITE?? PLEASE FAST

[Julie]

If you feel like you are being targeted at this very moment, call the police again.

Oh, and make sure the house is locked up.

[Keiry]

Ok youre not being serious right? if you are call 911 from your laptop . It sounds really creepy .

[maxwell_jay]

Do you have skype? Do you have a cell phone? Are all your doors and windows locked if so then she cant get in. If you dont have skype download it now. then call 911 or a close family member/friend. The cops are meant to keep you safe and if she cant get in and cant see u then she cant kill you so call them the moment you get skype. if skype cannot call 911 or u need to pay for it use this number 118002464411 that's bing 411 and its free, say your city and state then ask for emergency services or 911. Good luck.

[Cutie Pie]

go and make a skype address and call 911 and always keep your cell phone with you.

[TuTu]

2 days ago huh.. He must be dead by now.