Sanus - Premium Series Tilting Tv Wall Mount For Most 42" - 90" Flat-panel Tvs (BLT2-B1) Black - New

I highly recommend the Sanus Advanced Tilt Mount  for TV's over your fireplace, or an uneven surface such as stone.  The "scissoring" design allows the TV to tilt from left to right so it aligns perfectly parallel with an uneven surface such as stone. The post leveling screws come in very handy when  leveling your TV after its been mounted.  This Bracket retails for $130 at best buy, but can be found as low as $86.99 most of the time on Amazon.