Why can't iTunes locate my songs?

The songs you are looking for have either been moved or deleted.

When you add a song into i tunes, the actual file itself is still in the folder/directory (or wherever) it was before you added it to your i tunes library. You need to make sure that those songs stay where they were before you transferred them otherwise i tunes will not know where the files are to access and play them.

NOTE: i tunes does not store any files you add to it it is simply a way to organize your media and transfer media to your i pod.

Make sense?