Beacon Tracker and Sacred Shield Tracker have been combined into a single, Epic addon 'Paladin Tracker'!
http://wow.curse.com/downloads/wow-addons/details/paladin-tracker.aspx

BeT is a light-weight addon to easily cast, recast and watch the timer for Beacon of Light.

How to Use:

• Left click to Cast Beacon of Light on Stored Target, or Target/Select Target if first use
  
• Right Click to cast on current target, replacing stored target
  
• Hold Alt & Left Click to drag button
  
• Automatically hides for Paladins without BoL, and re-enables on Talent Switches!
  
• /BeT Config Enable/Disable the Warning or Expiration sound and other Options

Known Bugs:

• None Currently

Known 'Not Bugs':

• Due to Blizzard Secure Functions allowed in Addons, The "Stored Target" will not update while in combat - this makes it unable to "recast" with a simple left click if Beacon of Light is first cast after a Paladin has initiated combat. It will auto-set after combat has ended, however.

ToDo:

• Allow changing of sounds