Fast Development Joomla Modules
With decent mysql database skills, solid PHP programming skills and knowledge of the Joomla framework, you can develope Joomla modules rather quickly. The key is to build a template which can create queries and relational database queries for the tables in the Joomla framework. Once you have that, you can query and retrieve any results you want; just as though you were using php/mySQL with the exception of some slightly different methods to access the databse, objects, arrays and loops.
Once you have developed the starting module, you can test it with your desired Joomla installation. It is recommended to use various versions such as Joomla 1.5 and Joomla 2.5. Once all the versions work properly, all you really need to do is tweak the module's default.php or modulename.php. To keep it simple, the default.php or modulename.php file will be identical for each Joomla version.