June 12th, the way TV in the US is scheduled to switch from analog to digital. If you receive cable or satellite, you have no worries, you're fine. If you use an antenna (on top of the TV or on top of the roof), you will need a TV which picks up digital transmissions (most newer models do) or else a converter box.
It is too late to get coupons for the boxes. But if you have them, use them before they expire.
But you can purchase the boxes nationwide at Best Buy, Radio Shack, Target, Sears, Wal-Mart and other stores.
Click here for the government's website on the conversion.