Here are some of my favourite and most useful sites.

My Sites

A short list of the sites that I have created to date… Archer Trading, my first commercial WordPress site. A Joomla site created for the Eltham Model Railway Club (inc). Rinet IT, my own business. My first site using Joomla 2.5, an information site for obesity surgery. My first online portfolio to showcase my work. This new one has replaced it using WordPress. My personal website, my first one originally using Drupal. Drupal was chosen as it can incorporate Gallery 2.

It has now gone through a complete change. More details.

Joomla Resources

Here are some great sites to get started. There are also heaps of modules and plug-ins to choose from as well. The main Joomla site.
joomla developers Documentation about Joomla for developers.
joomlapolis The complete solution for your membership and social networking site.
joomsocial Another networking module for Joomla. Very similar in appearance to Facebook.
virtuemart An excellent e-commerce solution for Joomla
Joomla Shack A great source of professionally built templates.

WordPress Resources

Some WordPress sites to get started. Also worth checking out for WordPress is jQuery; a Javascript library which WordPress uses extensively. The home of WordPress