CAT

The syllabus of CAT and XAT are very similar in terms of Quant and Verbal.
Apart from this, XAT has GK and essay sections, which are taken into consideration in later stages once you clear cut-offs.
Decision making is the make or break section of XAT, CAT does not have any such section
Also, XAT introduced a new scheme of negative marking from 2016. This scheme had negative marking for incorrect responses and also for questions not attempted (>13 questions only), i.e. you could choose to not answer 13 questions. After this, you will start being marked in negative for every question you don't attempt. This is unique in XAT. This is not something to worry about as negative marking is very less probably insignificant in the final analysis.
Lastly, CAT is a computer based test and XAT is a pen-paper based test. Though the level of XAT has declined over the years, still XAT remains the only gateway to top tier institute of the nation which is XLRI.
XIBM, S P Jain, XIME are few institute which accepts XAT score. Every year, CAT has been under scrutiny for the way it was conducted their examination. XAT remains ethical in that sense. I suggest you to prepare well for CAT and probably in last month you can enrol for a decision-making course.

Stop thinking of it as a verbal section. The biggest mistake that you are making is that you are thinking Section 2 in CAT is the Verbal section. Apparently, it is not. Section 2 consists of 3 separate areas:
Logical Reasoning (LR)
Reading Comprehension (RC)
Verbal Aptitude (Critical Reasoning, Grammar, Vocab)
You need to prepare for all of them and if you are targeting 100 percentile, or for that matter anything above 95 percentile in section 2, you will need to be really good in two of the above three areas and above average in the third one. Find out the two sub-sections that you are strong in and work hard on the third one. You do not want to miss sitters in your relatively weak area.
Also, Word Power Made Easy (or any other Vocab building tool) is helpful in CAT but Vocab is not an important parameter. You barely get a couple of direct question on it but it makes your life easier in RC and other areas.
As far as preparation is concerned, I would highly recommend the use of previous year papers for both LR and RC. You need to understand the level of questions that are asked. It hasn't changed much over the years and it is unlikely that it will change drastically this time around.
For verbal aptitude, focus on critical reasoning. If you are good in stuff like para-completion, para-jumbles, fact inference judgement, summary then you can go a long way.

Practice Papers for CAT are:
Complete course Pack for CAT
Face to Face CAT Common Admission Test
Topic Wise & Year-Wise 27 solved papers
Topic-wise Solved Papers with 6 Online Practice Sets
Books for Verbal Ability & Reading Comprehension are:
Verbal Ability and Reading Comprehension -Arun Sharma
Verbal & Non-Verbal Reasoning -RS Aggarwal
Verbal Ability & Comprehension
Wiley's Exam Xpert MBA, Verbal Ability
Books for Quantitative Aptitude are:
How to Prepare for Quantitative Aptitude - Arun Sharma
Quantitative Aptitude Quantum - Sarvesh Verma
Quantitative Aptitude for Competitive Examination - RS Aggarwal
Quantitative Aptitude for CAT- Nishit Sinha
Books for Data Interpretation & Logical Reasoning are:
Logical Reasoning and Data Interpretation- Nishit Sinha
How to Prepare for Logical Reasoning for the CAT- Arun Sharma
How to Prepare for Data Interpretation - Arun Sharma
CAT Data Interpretation & Logical Reasoning -Gautam Puri
-
Books for Vocabulary & Grammar are:
Word Power Made Easy - Norman Lewis
High School English Grammar & Composition - Wren Martin
The Students' Companion - O' Brien
30 Days to More Powerful Vocabulary - Norman Lewis

Dear,
As per the eligibility, for CAT 2016 is down below:
The candidate must hold a Bachelors Degree, with at least 50% marks or equivalent CGPA
[45% in case of the candidates belonging to Scheduled Caste (SC), Scheduled Tribe (ST) and
Persons With Disability (PWD) categories], awarded by any University or educational
institution as incorporated by an Act of the Parliament or State legislature in India or
declared to be deemed as a University under Section 3 of the UGC Act, 1956, or possess an
equivalent qualification recognized by the Ministry of HRD, Government of India.Candidates appearing for the final year of Bachelors degree/equivalent qualification examination
and those who have completed degree requirements and are awaiting results can also apply.
All the best.