Joomla! Doc has a great documentation online that explains how to set up your development environment
This article provides detailed instructions for setting up your workstation for Joomla! development. Note that there are many possible configurations for doing Joomla! development. Any environment that supports Apache, MySql, PHP, and Subversion should work for writing Joomla! code and extensions.
This document provides step-by-step instructions for setting up and working with the Eclipse IDE. The example used and screen shots are for Windows XP, but the basic steps are the same for Linux.