Joomla cms has become such a popular content management system around the globe that some people and companies have invested time and money into building their own templates and interfaces specifically for joomla. A google search for "Joomla Templates" will reveal a wide variety of resources.
Across the internet you will find a range of templates for download including both free and paid versions. Normally a free version will require a link back to the template creator. Paid templates normally excuse such links. For more information a read me and license file will be available after downloading a template and will outline copyrights and rules of usage.
With a solid knowledge of html, css and general understanding of other web code you will be able to create Joomla templates. There is a wealth of information available and it is encouraged by Joomla themselves that people create templates. The Joomla Template Tutorial is a great place to start.
