MAT

You can check the below mentioned links:
https://www.shiksha.com/mba/ranking/top-mba-colleges-in-india-accepting-mat/2-2-0-0-306
https://www.shiksha.com/mba/colleges/mba-colleges-india?uaf[]=exam&ts=21699959&rf=filters&ex[]=5822&ed[]=et_20

MAT exam is conducted 4 times in a year. For 2017 admission, you can take exam in December or February. The last date for December MAT registration is November 26 and exam date is December 11. February MAT exam details may be announced after Dec MAT results. If you are prepared then go for December attempt.
I hope it helps.

there are many prestigious colleges which are accepting mat scores

You can call admission department or you can go to the website, write your query to the admission department.

No you would have to go through MAT,CMAT,GMAT or CAT exam since your final degree would be released only once you have cleared some exam affiliate to AIMA.

Join TIME coaching institute. It is the best coaching institute for the preparation of CAT exam. Also, it has delivered promising results.

There is not much difference in both the tests. Since, most students who appear for such tests are also currently pursuing other courses to facilitate the process. The tests are conducted on two different dates, thus giving the option to students to ensure their other exams don't clash with the dates of the tests.

EMPI is not recommended for its average placements and internship opportunities.
https://www.shiksha.com/mba/ranking/top-mba-colleges-delhi-ncr-accepting-mat/2-0-0-10223-306

Yes, it is compulsory to fill in college application form online. Also Christ mostly look into composite score and not the percentile. You need composite score of more than 600 to apply.