The main web site for X10 is http://x10-lang.org.
Of specific interest would be several X10 tutorials.
Prof Christoph von Praun has a nice X10 2.1 Tutorial with several good programming examples.
Information on how o run applications on the Three Musketeers cluster.
Please make sure you read notes on how to get performance with X10.
Code examples for X10 2.1