You can use the integrated launchers in Six Updater or Addon Sync.
However there are also other launchers out there, like the excellent Spirited Machine's ArmA Launcher.
Ongoing development 
ACE 1.13 RC5 [2011-12-09. Hotfix: 2012-04-27]
Stable
ACE 1.13 for OA [2011-12-23]
ACE 1.3 for A2 [2010-07-05] (Deprecated)
Dev blogs
Wheeled by Wagn v. 1.8.1