As for as i know there is no feature in qlikview to find out the Source Generator Qvw.
Developer who has developed the appllication should maintain seperate forlder for the Sources Generator Applications.
IF not you need to open all the QVW application and search (Ctrl + F) for the qvd genartaion code.
This doesn't help your problem right now but is maybe something to consider- when any change gets made to a production report, put a copy of the script into sourcesafe/TSF/SubVersion/some other versioning system. This will allow you to easily search it for the reference to the QVD. This is very useful for all sorts of scenarios - including the one that I hate the most:
DBA: I am changing field X to Y
QV developer: Oh ok I shall go and open every qvw and search the script
DBA: oh ok how long will that take?
QV Developer: Longer than it should :)
Whilst I remember it is best to put your connection strings into text files (use the Include function in QV to reference them), as going through each QVW to replace a string due to a server name/server IP change is a pain. One change in a text file is easier. I think when I have time I may make a list of these kinds of things. Granted, in each version of QV these kinds of things are getting easier and easier to manage.