Check out Transparency International's web site http://www.transparency.de.It provides a Corruption Transparency Index ranking corruption in the world. A few worth noticing countries/regions:
7. Singapore
13. UK
14. Germany
15. Hong Kong
18. USA
25. Japan
28. Taiwan
50. South Korea
54. Philippines
58. China
68. Thailand
72. India
82. Russia
It does not seem there is any correlation between corruption and democracy.