Does importing QSTK work?
import QSTK
How about QSTK.qstkutil?
If not this is most likely a sys.path problem. Please post the result of:
>>>import sys
>>>sys.path
It should look like:
[ [...], 'C:\Python27\Lib\site-packages', [...] ]
Another thing you can check, is if 'C:\Python27\Lib\site-packages\QSTK\qstkutil' contains a file named '__init__.py'. From the module documentation:
The __init__.py files are required to make Python treat the directories as containing packages; this is done to prevent directories with a common name, such as string, from unintentionally hiding valid modules that occur later on the module search path. In the simplest case, __init__.py can just be an empty file, but it can also execute initialization code for the package or set the __all__ variable, described later.