Adding to Mac OS X contextual menu Templates like on Linux Ubuntu
There are a number of ways you could do this.


You could use Automator to create new documents through a Service:
http://pauloppenheim.wordpress.com/2011/06/03/mac-finder-add-new-file-context-menu-item-open-source/
Use a context menu plugin, but these are less common on 10.6 and 10.7. You may need to run them using Shortcuts:
http://www.abracode.com/free/cmworkshop/macosx_10_6_snow_leopard_and_contextual_menu_plugins.html
Best of all, in my opinion, you can use a little known OS X feature called Stationary Pad. It's on the Get Info dialog of any file. The way you would go about using it is to create your template file, mark it as a Stationary Pad and then every time you double click it a new copy of that template will be created. Read more:
http://ignorethecode.net/blog/2009/05/31/creating-new-documents/