Columbia International Affairs Online (CIAO) is the most comprehensive source for theory and research in international affairs. It publishes a wide range of scholarship from 1991 onward that includes working papers from university research institutes, occasional papers series from NGOs, foundation-funded research projects, proceedings from conferences, books, journals and policy briefs. Recommendation: Use the advance search and limit your search to "working papers" or "policy briefs" for more relevant policy documents.
There are a good number of Pakistani think tanks that focus on a number of social, political and economic issues. Note that there will be a wide variation in terms of coverage, content, and searching functionality across sites. Some notable think tanks/groups to check out include Institute for Defense Studies and Analyses, Centre for Policy Research and Centre for Asian Strategic Studies--India. For a more complete list, visit: http://en.wikipedia.org/wiki/Category:Think_tanks_based_in_India. There is also a listing of Research Institutes (with some overlap): http://en.wikipedia.org/wiki/Category:Research_institutes_in_India