If you're searching for mp3's make a note of their file sizes & the bit-rate & be just a bit wary of those search results from T3 sources. If you see files in your search results that are the same size but a different bit-rate then you know something is wrong. Prefer to trust the results from non T3 sources 1st! See
T3 Spammers about this for music. And for movies, those wmv files that are spam advertising tend to come from T1 sources. Just a hint!