Got one on 1 Jun 12 that read:
"Congratualtion's, you are TORONTO's WINNER OF THE DAY. Go to http://www.walmart.com.wonacontest.com to claim your prize. You have 24 hours to claim!"
Had one a few weeks ago but did not check the number for bestbuy.
It is either a scam or an attempt to install a virus. The address was very peculiar so I did a test by searching walmart.com (a known good site) for a contest. There was none.
A reverse lookup on 411.com shows they are a company who bills $1.99 per phone message sent to you also so check your cell phone bills.