Virual IP

Hello,

Can you please tell me how to create a single virtual IP address to access the 3 PXC NODES in XTRADB CLUSTER

Sorry, it looks like your question was missed.
You may take a look at this article - using HAProxy for load balancing your PXC cluster:
http://www.percona.com/doc/percona-xtradb-cluster/5.5/howtos/virt_sandbox.html

Or here for more advanced configurations with VIPs:
http://www.mysqlperformanceblog.com/2013/11/20/add-vips-percona-xtradb-cluster-mha-pacemaker/