How to: Simulate Mouse and Keyboard Events in Code

http://msdn.microsoft.com/en-us/library/ms171548.aspx

SendKeys.Send Method
http://msdn.microsoft.com/en-us/library/system.windows.forms.sendkeys.send.aspx

MouseSimulator
http://stackoverflow.com/questions/5094398/how-to-programatically-mouse-move-click-right-click-and-keypress-etc-in-winform

mouse_event function
http://msdn.microsoft.com/en-us/library/ms646260(VS.85).aspx 
Imitate mouse click
http://social.msdn.microsoft.com/Forums/en-US/csharpgeneral/thread/ebe2c146-03ca-40eb-990d-093fbd3d4886/