There are two possible things that it could be. Either it may not have installed correctly or your python path is not setup correctly. I'm not sure what OS you are on (by the code output I'm guessing windows),
To verify it installed correctly do a search from the file explorer for 'SimpleCV' and see if it is found under the python libraries directory. If so then it probably installed and then you just need to do:
SETX PATH C:/Python27/;C:/Python27/Scripts/;C:/OpenCV2.3/opencv/build/x86/vc10/bin/;%PATH%
SETX PYTHONPATH C:/OpenCV2.3/opencv/build/python/2.7/;%PYTHONPATH%
If that doesn't work you may have to install manually:
https://github.com/ingenuitas/SimpleCV#windows-7vista