19 November 2017
There is no change in syllabus for ca final May 2018 attempt vis-a-vis previous attempt for old course except for DT & IDT subjects. But yes, you might have to go through last 6 months amendments (Which will be highlighted in upcoming latest RTP) for FR, Audit and Law. There is ZERO amendment in SFM and AMA. Also, as you said, there are changes in DT (new Finance Act, 2017) and in IDT (GST instead of Excise & service tax). Also, i advice you to go through this link of icai for applicable edition of study material: https://resource.cdn.icai.org/47270bos37073.pdf
19 November 2017
Your welcome deepak. A friendly advice, never ever believe YouTube/WhatsApp/Facebook advisory. There are plenty of wanna-be new faculty etc who spread wrong info for publicity. Always just rely on icai.org
20 November 2017
If you are asking to purchase CA institute book (as mentioned in link in my first reply), yes you can purchase immediately. If you want to purchase books of specific private authors, some might be out in market, some not. You need to do a survey yourself..