detector.py

import os, sys
wordtolook = raw_input(">")

for root, directories, filenames in os.walk(os.getcwd()):
    for filename in filenames:
        if os.path.join(root,filename) != sys.argv[0]:
            fileobject = open(os.path.join(root,filename), 'r')
            if wordtolook in fileobject.read():
                print "{0} at :{1}".format(wordtolook, fileobject.name)
            fileobject.close()