First, you will have to install the 3rd party clusterware software. Contact the vendor for help there.
Next, you will need to install Oracle's Grid Infrastructure cluster software. The GI Install Guide can be found here for your platform.
Then you can install the Oracle database software and create your database.
You are required in 11g to use Oracle's clusterware even if it sits on top of a 3rd party cluster solution. Me personally, I don't like two clusterware solutions in the same stack so I ditch the third party one and use Oracle's.
because of cost, i have deployed VCS for Oracle DB in Active/Passive. you have to edit some VCS scripts. you install oracle db single instance NOT oracle clusterware. see link above.
if you want to installed RAC...i will advise not to OVER KILL CLUSTER configuration!. just thick with only oracle clusterware.