The other day I wanted to move away from the Apache httpd server to Nginx. It was not that Apache did not do the work, but the lower the footprint of a service the more you can have running on a single server / cloud instance. And if I would get a peek of traffic I will have more "power" to give.
So I opened a repository at GitHub at https://github.com/roheim/centos-nginx-drupal. That should give you a basic setup / template to set your sites up and running with nginx.