Here you can find collection of Vаkатaka inscriptions.

See, also, my papers, based on research of Vakatakas inscription:
Structure of the Early Indian Land-Grants and the Problems of its Interpretation. In: Oriental Studies in the 20-th century: Achievements and Rrospects, vol.1, pp. 23-24 (abstract of paper, which I read on ICANAS in 1997);
(in russian) In: International conference "Pamyatniki duhovnoi, materialnoi i pismennoi kultury drevnego i srednevekovogo Vostoka". M., 1995, pp.42-44 (abstract)
Detailed research included in my book "State in Ancient India" (on Russian). M. 1997. (Deponiered in INION).
Partly it included in my part of "State in the History of te Society. To the Problem of State Criteria". M. 1998, M. 2001 (Second edition), in Russian, which will be publicated in e-form some times later, after realization of the second edition.

See also the TABLE of immunity formulas in Vakataka inscriptions with comm.