Hi Jayesh, welcome to JavaRanch.
You can get the SCJP Study Guide by Kathy Sierra and Bert Bates. Its an excellent book and since you have knowledge of java
you should have no difficulty in understanding the content. After that you should try out some mock exams and if you score well on them, you can go for the real exam. You can find more information in ScjpFaq and
ScjpMockTests pages...