Howard van Rooijen has an excellent article on setting up Simian to detect duplicate code. Then he takes the next step and creates MonkeyWrangler, an add-in that takes the Simian output and converts it so that you can double-click on the text and Visual Studio will take you to the file and line of code!

Found 9 duplicate lines in the following files:
 D:\Projects\Conchango\Conchango.Gluon\Conchango.Gluon.Plugins.Interface\ConfigSettings.cs (163) 171
 D:\Projects\Conchango\Conchango.Gluon\Conchango.Gluon.Plugins.Interface\ConfigSettings.cs (141) 150