Hi Chandana,
For Study Material, most of them suggest "Head First EJB".
It is also good to go through the
EJB Specification.
Many people have suggested SOFTSCBCD simulator. you may also consider
Whizlabs.
For free mock exams you may login into
www.ejbcertificate.com For more information on mock exams look at
SCBCD Links Hope it helps
SCJP,SCWCD,SCBCD,SCEA Part I