Please have a look at the following post
http://www.nutrixinteractive.com/blog/?p=73. It is details of a new tutorial I have written for a publication over here in the UK (available for purchase online though). It covers building a simple Flex application retrieving and sending data to a MySQL database. The application is built on the PureMVC framework and give a really good insight into using PureMVC with Flex and ColdFusion for an application easily adapted for a real world scenario!
Cheers,
Simon