There is a huge literature on this subject. You can start with the originators of the tradition with just these names in Google or Wikipedia: Henry Lawrence, John Nicholson (there is an oblisk erected to his memory outside Islamabad), Herbert Edwardes (Edwardes College Peshawar), James Abbot (Abbotabad, NWFP), John Jacob (Jacobabad, Sindh). Also, early outfits like Hodson's Horse, Daly's Horse, Coke's Rifles, Jacob’s Horse, Lumsden's Corps of Guides.

Three famous ones from post-1857 years are John Lawrence (rose from tax collector to Viceroy), Robert Sanderman (creator of the concept 'hearts and minds' in the 1880s), Francis Younghusband (invader of Tibet and Political Agent in Gilgit and Kashmir).

These are good secondary sources:
Allen, Charles, Soldier Sahibs, John Murray, 2000.
Allen, Charles. God’s Terrorists. Little, Brown, 2006.
Loyn, David, Butcher and Bolt, Hutchinson, 2008.

Allen is a historian, Loyn is a journalist (BBC South Asia correspondent). Both have a good selection of primary sources in their biblio.

Most of the district gazetteers were written by British political agents and commissioners. Many are still available. But don’t look to these folks as guides to improved governance. Their purpose from 1757 to 1947 was plain and simple: protect the state and its profits. Their successors in Pakistan continued that tradition up to 2002 in the settled areas, but remain in the tribal belt using the British Frontier Crimes Regulation as their tool to bludgeon anyone they want. You can find a similar framework of collectors, commissioners, political agents in nearly all of the former British colonies. This institution has mostly retarded democratic growth, particularly local governance, everywhere it was planted.

By the way, Sanderman's 'hearts and minds' amongst the Baloch was created precisely to counter the 'butcher and bolt' policies that 'Henry Lawrence's Young Men' started with the Pashtun, particularly as practiced in Waziristan and Swat. Heard of those places lately? It seems neither tactics nor strategy have changed much in more than a century, so what have we learned?