» Thu Jul 07, 2011 8:34 am
The best you can do is add them to your library.
On the Steam main UI, click 'games/add a non-steam game to my library'. Let it search and then find the game on the list and click add selected programs.
You'll be able to launch them through Steam (Though you may get wierd results with some games) but you won't get any other benefits of Steam.