How can I restore my iTunes library?

I have about 1400 songs in both my iTunes library and in my iPod. I saved all my music in iTunes into a library called Music. The other day when I was cleaning out my computer I (ever so foolishly) deleted the folder, thinking that it was the Windows default folder. Now whenever I try to open a file (song) on iTunes, a window pops up saying "The orginal file cannot be located.". I may have deleted the original file on the computer, but I still have all of the files on my iPod. I'm thinking about getting a new iPod and I still want all of the music on my current iPod. Is there any way I can get the music from my current iPod back into my iTunes library? Thanks!