I dont know how i did this but all the songs in my library weren't there. I looked everywhere on my computer and i came to the conclusion that they were deleted so is there any way for me to get them back. Now that they are deleted the songs on itunes don't work and it would suck to have to download all those songs again.

Use your computer's search to see if they're still around somewhere. If you're using LW 4.12.6 or earlier, when files are deleted from LW's library, they don't go to the recycle bin first
The 4.13.0 beta version does send files to the recycle bin if they're deleted from LW's library

Have a look through this sticky for file recovery advice
Deleting files from LW library - Don't!! File recovery advice