Deepali,
Unfortunately NCEES is not very forthcoming when it comes to scheduled code updates. They claim that they do not want to cause confusion by having more than one published list of design standards, so they never announce code changes more than six months in advance. This is a big problem for people like you trying to prepare a year in advance.
For reference, NCEES adopted IBC 2009 (and the associated reference standards including ACI 318-08, ACI 530-08, etc.) starting with the April 2012 exam. They announced this change immediately following the October 2011 exam. If they are to maintain the same 3 year lag, we might expect that NCEES will adopt IBC 2012 beginning with the April 2015 exam. This is just a guess though, and it could be another year before they actually get around to updating the exam design standards. NCEES won’t make any official announcements until after his year’s October exam.
Regarding buying the Structural Engineering Reference Manual (SERM), I’d say go ahead and buy it now (or whenever you plan to begin studying). Even if the codes are changed for the April 2015 exam, it will take PPI several months, maybe a year, to update their books following NCEES’s announcement, so it’s unlikely that there will be an updated SERM for you to use prior to April 2015. In general the codes don’t change much year-to-year (especially the sections that are most likely to appear on the SE exam) so the book will still be very useful, even if it is technically out of date. One big exception is that the wind provisions for ASCE 7 have undergone major changes between the 05 and 10 versions, but I don’t think this renders SERM worthless--wind load calculations are only a very small part of this book. When studying from the SERM, I recommend following along with the relevant code sections anyway. This way you’ll be able to pick up on anything that might have changed.
I would however recommend waiting to buy the design standards. You’ll definitely want to have the up-to-date versions for the exam, so best to wait for NCEES to publish the list after the October exam.
The NCEES practice exam book has extensive code references and is very representative of what you can expect to see on the actual exam. But NCEES hasn’t even gotten around to updating this book for IBC 2009 yet. So don’t expect a timely update to this book once new changes to the design standards are announced. It’s still a worthwhile purchase in my opinion though—just make sure to check their solutions against the up-to-date design codes as some solutions may be affected.
Other references I recommend reviewing (beyond the NCEES list design standards, SERM, and the NCEES practice exam) are:
2009 SEAOC IBC Structural/Seismic Design Manual, Volume 1
A Structural Analysis Textbook (such as Structural Analysis by R.C. Hibbeler)
16-Hour Structural Engineering (SE) Practice Exam for Buildings (full disclosure: I wrote this one, so my opinion is totally biased)
NCSEA also publishes a detailed list of available study materials here:
http://www.ncsea.com/downloads/files/Education/SE%20Review%20Course/SE%20Exam%20Study%20Guide.pdf
This is way more than anyone would need, but you can pick and choose references from this list based on what you think you need more help with.
If you’re looking for more general information about the exam and how to prepare, the introduction to my book is available for free online here:
http://ppi2pass.com/Docs/bookInfo/STBDPX/STBDPXintro.pdf
Good luck with your studies!