If this is just for a proof of concept I would use one of about 7 options.
- Red Hat Openstack (Using Packstack) http://openstack.redhat.com/Quickstart
- Ubuntu using Using Devstack http://devstack.org/
- VOVA (vmware appliance that runs on vSphere) http://www.vmware.com/go/openstack
- Puppet Module https://forge.puppetlabs.com/puppetlabs/openstack
- Chef Openstack http://docs.opscode.com/openstack.html
- OpenStack with Foreman http://openstack.redhat.com/Deploying_RDO_using_Foreman
- Ubuntu Official OpenStack Getting Started https://help.ubuntu.com/community/UbuntuCloudInfrastructure
Step by step Installation Guides:
- http://docs.openstack.org/havana/install-guide/install/apt/content/
- http://docs.openstack.org/havana/install-guide/install/yum/content/
- http://docs.openstack.org/admin-guide-cloud/content/
Per your comment:

A production deployment design really is based on what your needs are, the type of workloads, and the amount of resources available (this could be both hardware as well as future capital expenditures.) Questions to think about are what are the top business requirements?
Example: By priority
1. Highly Available (stable cloud infrastructure)
2. Scalability
3. Performance
4. Efficiency
So if this were the business requirements one would assume you would want to prepare for failure in your cloud infrastructure. This would include failover identity, imaging, storage, compute (this is to be assumed in a multi tenant environment), and networking. I didn't cover all of them, but it gives you a picture of what it might look like.
I'm sure different Architects would have different opinions on what is the best route to production deployment. Again, it's based on need. You could for a preliminary production environment deploy 2 "controllers" that house everything but your compute nodes for HA. However, you could suffer some major performance issues, manageability might be harder, and depending on your networking needs Neutron might be best on it's own HA pair. Have I lost you yet?
If your under the gun and time is of the essence I would consult with a professional services group such as Mirantis, RedHat, Rackspace, or Canonical. Also, I would probably do a fair amount of training so you can support this production environment sufficiently.
I found this video from the OpenStack Hong Kong summit really interesting around OpenStack in production:
http://www.openstack.org/summit/openstack-summit-hong-kong-2013/session-videos/presentation/deep-dive-into-the-cern-cloud-infrastructure
This question is really too broad to be answered here. There are lots of installation guides out there that will walk you through an OpenStack install, both manually and using a variety of deployment tools. You'll get much better answers here if you ask focused questions for which one can provide a specific technical answer.
Yes... their are too many helps available, but none is step by step for a novice to build cloud... Assuming I have a XEN server 6.2 installed on a bare metal, how should i proceed with installation & configuration of various components of Openstack. Which component should be installed first.... Even if you provide a link / pdf this would help me to start. I am planning to deploy Openstack on Ubuntu 12.04 LTS version.
I would start with the Ubuntu installation guide on the OpenStack wiki: http://docs.openstack.org/trunk/install-guide/install/apt/content/