At this time you cannot block numbers from calling, It is being worked on and we should see something soon, In the mean time download the silent ringer here; http://community.sprint.com/baw/servlet/JiveServlet/download/2019-25074-136712-3070/silent.mp3
Use this uploader to send it to your phone; http://rumkin.com/tools/sprint/
Add the number you want to block to your contact list, Apply the silent ringer and you won't be bothered when they call.
Yes you can but it is extremely time consuming. Go to SETTINGS click PARENTAL CONTROLS click ON create a new code click RESTRICTION select ON for voice click ALLOWED NUMBERS then add every single contact you wish to be allowed to call you......all other numbers will not be able to call.
Effective *Monday August 30*, Sprint customer care can assist you with requesting incoming or outgoing call blocks. Up to 50 phone numbers can be assigned to the block list. This feature is separate from the current text-blocking capability. (http://support.sprint.com/support/videos/Services_video__Blocking_Text_Messages/case-wh164052-201006... Additional blocking features will be available in the near future including the ability to create "allow lists" and the ability to perform your own phone number blocks through our online self-serve tools. To block phone numbers, please contact your Sprint Care Rep.