For general knowledge and legal aptitude which books I should study?

You have no doubt heard of a library where they catelogue various topics

Ill tell you the book series I like will that help?

Go to the legal section at your uni or public library. The Dewey Decimal cataloging system number is 340. Or check with a librarian who will help you with basic books to study.

What is the pattern of clat test? Will they have different patterns of questions for different universities? Is patern is same for all universities? Please kindly answer me as early as possible.

Which books I have to study for better performance in comprehenssion and current affairs for clat-2012?

Go to a uni or public library for help with these questions. Can you do that?