Wide World of Women

Has anyone ever had a song disappear from their itunes queue? Suddenly I can't find a specific song for the life of me and I know I didn't delete it.

Did you try looking for it using iTunes' built-in search function?
If you know you still have the original file, open it with iTunes. Either it'll re-add the song to the library, or perhaps reveal where it is in your library if you accidentally relabeled it somehow.

iTunes always gives you a warning if you try to delete a song from the library, unless you disabled those warnings.