Deleted xml file

Hello,

by accident i deleted my itunes library xml file ... because i was trying to copy songs from my ipod to my mac.. and apparently its not the same way when i used to do it with my pc .. soooo now it's not letting me copy any kind of music into my itunes bc theres an error and it says that my library cannot be found .. how can i restore that file so i can put music in my itunes ?!