Preparing for June 2012 exam with 2011 books

Can I study the LOS from 2011 study materials for june 2012 exam?

No. You cannot. There are a lot of changes in the syllabus from 2011 and 2012. Plus, if you are starting to study now, it is a little too late imo.

I attended all weekly coaching classes for CFA level 1 which was started in Nov 2011 and I have solved few test papers also. I want to go through the LOS thoroughly for which i am refering 2011 books. Pls let me know if the changes are with only economics as a topic or with other topics also. So that I can organise the required books. I have taken leave specially to cover up everything before the exam. How many hours should I devote everyday for June 2012 exam?

All of Econ is different and some changes in FRA also.

By this time, most of us would have finished the studying part and would be in the reviewing stage. You need at least 2 weeks of reviewing, solving questions, and practise exams. The time taken depends upon the individual. You will have to devote a minimum of 15 hours per day.