How can you hide an IP address?

My sister has been corresponding with a guy for the past year who lives in Russia, whom she met through an online live blog site. They correspond daily either through email or Skype. Today she received a phone call from Fedex saying they had a package to deliver to her. My sister was confused by this call because she wasn't expecting a package. She drives down to the Fedex office to discover that this guy from Russia had sent her a package. Of course she left the package at the Fedex office and was freaked out by this entire situation. She never gave him her address, only her phone number. This guy had placed an address on the package that was about three miles away from my sister's house. How in the world did this guy find out come even remotely close to where my sister lives and what can she do to hide her IP address?