March 2003 - Getting started and learning...
A good place to start to learn about AO-40 is the Amsat AO-40 FAQ. Next, I read G6LVB-Beginners' Guide to Receiving AO-40. Also, AO-40 operation by W0LMD, provides a good overview of many aspect of getting on AO-40. The AMSAT-ZL website has some other interesting pages related to AO-40 as well.
If you have access to old QST's, you will find some good articles there as well. The July 2001 issue has an article titled 'Getting Started with AMSAT-OSCAT 40' and the September 2001 issue has 'OSCAR 40 on Mode U/S - No Excuses!'
Between all these, you get lots of other interesting links to broaden your horizon.