I would say the most common way of notification of a win is an email, if there is a notification at all.  Lots of times the prizes just show up at your door or in your mail box.  Occasionally there will be a phone call, but those are few and far between and usually for the really big prizes.  With instant wins, mostly you find out when you play with a confirmation email to follow.

Thank you both for the quick responses!  I was just wondering because I have started to get a few random calls since starting SA. One several times a day but when I pick up there is no one there may not be related to the sweeps.  I figured Id get a general idea of were the legit notifications so I could ignore the fakes!  Thank you so much and hopefully we all when big and soon!!!!

this is true never thought of that!