Hi,
IIMs offer Fellow Programmes in management (FPM), which is equivalent to PhD. You'll have to appear for CAT inorder to apply for the same. It is a 4-year programme. The IIMs have called for FPM applications now.
Alternatively you can opt for Doctorate Progammes. Many of the universities in India offers Doctorate programmes in Management. Universities abroad also offers similar programmes. For Indian univrsities you'll have to qualify UGC-JRF or other departmental tests in order to secure an admission. For universities abroad you'll have to appear for GRE/GMAT and TOEFL/IELTS. There would be fees in some universities, while others would pay you a fellowship and.waiver.
Identify the university/institute you'ld like to do your PhD. Check for their past thesis and publications, strength of faculty members etc before applying for PhD. It would normaly take about 4-5 years to complete PhD. There would be coursework, classes and finally resarch with theseis presenation and defence.
Please check the concerned university Web site to get more details about the fee, duration and courses offered.
Cheers
-----
sree