well if you are new to EJB technology let me give you my humble advice. Forget about EJB 2.0. It was a technology which made so complex to write enterprise applications. As a result new light POJO framework came up and gained so much popularity that in the EJB 3.0 specification they adopted lots of those concepts to simplify EJB development. Learn fresh EJB 3.0. If you want to give it a try in the link below there's a simple tutorial about them. Regards Francesco http://www.mastertheboss.com
I also found OReillys Enterprise Javabeans 3.0 (5th Edition) by Burke and Monson-Haefel to be brilliant. It comes with a workbook for Jboss so you can go through the examples.