Hard drive crashed. How do I get OS and boot disk from Dell?

Dell Inspiron 15Z model 5523 laptop less than 2 years old.  Locked up during a Windows update.  Refreshed it and lost all my programs.  Downloaded Firefox accidentally from a bad site and it was bundled with malware.  So I refreshed the laptop again.  Had everything working and then later that day it just quit.  Locked up and when I rebooted, it said no hard drive could be found.  I have a new hard drive and someone who can replace it for me, but how do I get my Windows 8 (paid for with the computer) and a boot disk from Dell?  Thanks!