I hail from a state called "Andhra Pradesh" (AP) in South India. For a long time, I have been trying to find out more about the origins/roots of the many communities in the state. This link http://indculture0.tripod.com/tindex.htm has some interesting piece of information on some of the more well known castes/communities in the state.
I wish there was more, as Indian history has always been sort of filled with black-holes, and the only history we know is that was transmitted by an oral-tradition spanning over thousands of years, but written down in the last 2500 years. South India has been an even bigger mystery, very little information seems to be available around the origins of this population or the languages, apart from the now-discarded AIT (Aryan-Invasion theory), or the Elamite-Dravidian connections.