The PLE Conference website(s) have found a new home and we are still working on it. This is now a portal from which you have access to the past, present and upcoming PLE Conferences.
Here is the link to the last PLE Conference 2014.
For information about the previous conferences you can go to the archives below for 2013, 2012 and 2011. The website of the first PLE Conference 2010 is still up and here is the link: http://pleconference.citilab.eu/.