I doubt any one of these is exactly what you are looking for, but you can excerpt from them, as necessary.

Afghanistan Research Reachback Center, My Cousin’s Enemy is My Friend: A Study of Pashtun “Tribes” in Afghanistan, TRADOC G2 Human Terrain System 5 – 24 (United States Army 2009) available online.

Thomas Barfield, Weapons of the not so Weak in Afghanistan: Pashtun Agrarian Structure and Tribal Organization for Times of War & Peace, Yale University (February 23, 2007) available online.

Antonio Giustozzi and Noor Ullah, "Tribes" and Warlords in Southern Afghanistan, 1980-2005, Crisis States Research Center, Working Paper No. 7 (London School of Economics, September 2006) available online.

Bernt Glatzer, The Pashtun Tribal System in Georg Pfeffer, Deepak Kumar Behera, Contemporary Society Tribal Studies, Volume 5, The Concept of Tribal Society 265 (Concept Publishing Company 2002) available online.

Olivier Roy, Afghanistan: Internal Dynamics and Socio-Economic Dynamics and Groupings, 4 WRITENET Paper No. 14/2002 (March 2003), available online.

Susanne Schmeidl and Masood Karokhail, The Role of Non-State Actors in "Community-Based Policing' - And Exploration of the Arbakai (Tribal Police) in South-Eastern Afghanistan, 30 Contemporary Security Policy 318 available online.