Q. Where can I find some articles that argue for or against capital punishment?

The ideal place to find articles on this subject are the library's Controversial Issues databases.  You can view them through the list below.

CQ Researcher, Issues & Controversies, and Opposing Viewpoints are all good places to find overviews of the topic, and the common arguments about it.  Opposing Viewpoints also has numerous articles in which people argue specific positions about the issue.