Dr.K.P. Sastry surveyed south India and prepared reports on cultivation of medicinal and aromatic plants in different States. He has addresses of several farmers cultivating MAPs.
The problem is the absence of agencies collecting accurate information from time to time. For agricultural, horticultural and forestry species, universities and departments exist with offices spread all over the country to collect and regularly update the data. In addition the trade volumes, exports, market yard auctions provide estimates. Unfortunately such sources are lacking for MAPs. Though departments of AYUSH exist in all the States, collection and updation of cultivated area is not their thrust area. In many States aromatic plants are out of the scope of the AYUSH department. The horticulture department, spices board etc. tend to club some of the aromatic species with ornamentals or spices. CSIR-CIMAP should take leadership role in collecting, collating and updating this information.
To revive your discussion, Dr. Rajendra Gupta gave some data in his chapter on medicinal and aromatic plants in Dr. K.L. Chadda's book on Advances in Horticulture volume on Medicinal and Aromatic Plants. This is old data now. Dr. K.P. Sastry mentioned few days ago that NMPB sanctioned a new project to survey 6 States. Did you contact him?