How can I tell whether the song is censored or not
 

When I download mp3's I find that some of them r censored. IS there anyway of finding out whether the song is censored before you download.

Nope.... the only way I can think of is if someone was kind enough to add either "censored" or "uncensored" as part of the file name. If you're looking for the uncensored version of the song, you could always add the word "uncensored" to the song name you're searching for and see what you come up with.