I made a playlist on Limewire but when it turned to a new song, it said song was not available. I clicked on delete to get rid of it, it confirmed that I wanted to delete the song... I clicked yes, the screen froze up for a couple seconds... then all of my songs disappeared. This has happened before, I just dont understand why. HELP!

Do you mean that all the songs in your playlist disappeared from the playlist, or disappeared from your library?

I'd suggest disabling the LW player (really, it's not very good) & making something else your default music player

I mean all of my songs are actually gone. I dont know what happened... its so weird. I cant find them anywhere

Use your computer's search to look for some of the missing file names.
If you've accidentally deleted things from your library, they're gone I'm afraid (unless you're using the new beta version of LW). You'd need a file recovery program to try & retrieve them. The thread below has some advice about this
http://www.gnutellaforums.com/showthread.php?t=49851