I frequently do this by getting the .LS files and using Xplorer2, http://www.zabkat.com/, to search for text in the files. This will generate a list of files that contain the text you are searching for.
Here's a description of the find text in files feature. http://www.zabkat.com/x2h_2.htm#br_grep
Also, if you want to go all out, you can look into RefView which has a ton of usefull features.
http://www.thinkbotsolutions.com/refview/features/