how do I find out if a "work at home advisor" job offer is a real job for apple inc.

How can I make sure that the job offer I have recieved from Apple Inc is a real job? I reieved an email from someone from HR Apple Inc stating that they have reviewed my application and I fit what they are looking for. I have completed all necessary steps for "work at home advisor" and I was emailed this past monday stating that I will be starting on the 28th and I will be recieving my contract and other documents and my "Imac". I havent recieved anything as of yet and I have called and emailed the person several times with no response. Im getting concerned. Can anyone please shed some light on this for me? Thank you