Lost most of my library and playlists ever since my battery died.

Hey there,

Most of my iTunes library seems to of disappeared. I have no playlists, no purchased playlist etc. All of my Tv Shows have gone too,

My battery died the other night, when i switched my Mac back on the following morning most of my content was gone. (iTunes only)

Any idea why this has happened?

Is it possible for me to retrieve my playlists and content etc?

Thanks,

Chris!