The World Bank provides data in its Actionable Governance Indicators at http://www.agidata.org/site/ .
United Nations -- Data on the governance indicators related to the Millennium Development Goals is available at http://unstats.un.org/unsd/mi/mi_goals.asp .
Transparency International ( http://www.transparency.org ) produces an annual report -- The Global Corruption Report which is available with a number of other reports in .pdf format are available at http://www.transparency.org/whatwedo/publications .