i thought the "blocked number" only came up on your caller ID. if you record the time of the phone call and check it with your phone bill/statement it will list the number. my g/f had a problem with one of her ex's a few yrs ago, he was calling and harrassing her saying he was going to kill her and shit from a blocked number, so we just checked our cell phone bill and it was on there. within a week she had a restraining order for harrassment. the phone calls stopped immediately. but theres always a way to find out what number they are calling from. unless they are a secret organization with the government.