11 March 2015
no need to buy new books except for law and audit as there are changes in it and for dt you can refer supplementary as posted by icai on website for all ammendments by finance act 2014
11 March 2015
Rightly pointed out by Ankit you must buy new book for Tax due to change in assessment year. Only supplementary material will not be enough. You need to practice problems as per provisions applicable for AY 2015-16. In Nov 2014 AY 2014-15 was applicable.
While buying book of Law and Audit ensure that they are applicable for November 2015 term. Changes will also be there in accounts due to Companies Act 2013 so take note of that too. Accounts changes can be covered from Practice Manual and RTP of the relevant term.