Enterprise JavaBeans 3.0, Oreilly EJB 3 in Action You can start off with any one of these books. I used EJB 3, Oreilly first(not brain-friendly but explains a lot of things) and then EJB 3 in Action (close to Head First). Pro EJB 3 Java Persistence API (must to have) MZ's Guide (really good) Enthuware simulator (I would definitely recommend this one)
About Exam, It was very easy than i expected.
About my preparation: In addition to the books, did some hands-on (not the ones given in the books) took notes while going through the books and mock exams; helped as a last-minute guide. referred the specs for the topics mentioned in Enthuware simulator.
Thanks to all ranchers and all the best for your certifications.