i normally open up a command prompt and use find / dir
I have F:\Pillage\_Movies\Movie.Features.Source.EncodeQuality-Group\Imdb Movie Name..avi (and .tbn, .nfo)
so I do the following
Start -> Run -> CMD -> Ok (Vista users, all programs -> accessories -> Command prompt)
DIR /B/S *.avi *.tbn *.nfo > F:\Rawlist.txt
then due to my naming format (Movie.Part1 Movie.Part2, etc) I remove the part2 entries
find /v ".part2.avi" f:\Rawlist.txt > F:\NoPart2.txt
Then Usually i'll open up a text editor, notepad, ultraedit, etc and do a Replace, changing \ for , (comma) then save the file as MovieList.CSV and open up in your favourite spreadsheet program (excel/openoffice/etc)
You can use data validation rules or your own eye to check each entry, or another easy method is to use a formula to remove the last 4 letters/characters from the CELL with your moviename.avi and moviename.tbn list and then just highlight duplicates, and look for the odd ones out.
ie; in excel =LEFT(A1,LEN(A1) -4)
Note: this assumes your in another "1" cell, ie; B1 and that A1 contains your data source.
I guess after writing down how i do it, I Agree with OP - can you include support for this...haha