1) Go to Google's Advanced Search Page: (link below)http://www.google.com/advanced_search?hl=en
2) There are 4 blank fields at the top of the page. In the first blank, "with all of the words", put whatever song/artist/style you want to find.
3) In the second, "with the exact phrase", put "PARENT DIRECTORY".
4) In the third, "with at least one of the words", put ".mp3 .wma .ogg" (any file format you want to search for you can include here).
5) In the fourth, "without the words", put "cd debian linux" (this helps filter out useless pages).
These are instructions for if you want to search for mp3's. You can use this method for software, movies, images...the possiblities are endless. Just leave the "PARENT DIRECTORY" and "cd debian linux" fields the way they are, and change the other two to reflect what you are looking for.
Another tip, try putting "index" with whatever else you are searching for in the top box. Like, if you were searching for primus mp3's, instead of just putting "Primus" in the first field, try "Index Primus". This seems to weed out some crap pages.
You can also substitute "Index" for "PARENT DIRECTORY".
For videos you might try adding more file formats to your search. Like ".avi .mpg .mpeg .asf .asx .wmv .rm .ram .mov"
Only snag is that google, has it limited to 10 terms, play with it. Google Advanced Search