The Targeted Killing topic is rich with resources on the world wide web. A simple Google search will turn up all kinds of really useful information addressing both sides of the issue, from a legal, moralistic and utility point of view. You will learn much about Just War and read rants about the constitutionality of targeting U.S. citizens abroad.
Nevertheless, it is the end of the debate season so I have pulled out some random sources and scatter them among the hardy debaters who will take on this magnificent topic. These are not the best papers, nor are they particularly neutral in their respective points of view. Still, they are unrestricted sources and free to view. It will be interesting to see what arguments eventually work and which fall flat. Good luck.
Targeted Killings, Council on Foreign Relations, Jonathan Masters, February 28, 2012
Mainly information on the legal & political aspects and methodology. U.S. specific.
The Targeted Killings Debate, Council on Foreign Relations, Matthew C. Waxman June 8, 2011
A compendium of views
Targeted Killing in U.S. Counterterrorism Strategy and Law, Brookings Institute, Kenneth Anderson
The erosion of legal grounds for TK - pretty much a repeat of a previous article published in 2009 and posted at the Hoover Institution here: http://www.hoover.org/publications/defining-ideas/article/5281
TK is bad
Targeted Killings, American Civil Liberties Union, Apr 28, 2010
U.S. Must Explain Targeted Killings of Its Own Citizens, American Civil Liberties Union, Nathan Wessler, Oct, 2011
Lots of internal links in the article.
Targeted Killing: Death Without Due Process, American Civil Liberties Union, Suzanne Ito, Aug 2010
Ms. Ito debates Neg with internal links in the article
Do Targeted Killings Work?, Brookings Institute, Daniel L. Byman, July 2009
Mr. Byman is not a fan.
In Wake of Al-Awlaki’s Death, U.S. Needs to Come Clean on Targeted Killings, Human Rights First, Daphne Eviatar, Oct 2011
What if other countries used drones to kill in the U.S.?
Obama's Targeted Killings in Yemen, Cato Institute, Nat Hentoff, Feb 2010
A low key protest of sorts.
By Any Name Illegal and Immoral, Yael Stein, 2003
Full text of Yael Stein's condemnation of the TK used by Israel
Targeted killing and the 'War on Terror', AlJazeera, Jonathan Hafetz, 2011
Justifying TK is a slippery slope.
TK is Good
The Morality and Efficiency of Targeted Killings as a Policy Tool, Ohio State University, Abraham Kanter. 2007.
Mr. Kantor's Sr. Honors Thesis with a consequentialist moral theory.
Targeted Killing, Daniel Statman (undated)
Moral theorist Statman looks at both sides and defends the practice.
TARGETED KILLING : MURDER, COMBAT, OR LAW ENFORCEMENT ?, Jeff McMahan
Moral theorist McMahan - 'nuff said I think