How to block phone numbers?

[swiley]

Here they seem to be spoofing random local numbers (I've gotten angry calls from other people when my number has been spoofed) so if you block the numbers you won't stop the calls and you'll miss calls from people in your area code if they ever try to call you.

My solution is to just never pick up from unkown numbers and let them go to voicemail, this is almost never a problem and eventually they assume your phone is no longer active.