why does a little icon appear on next to my itunes song and it doesnt let me see!

This means that the file that iTunes is trying to read is no longer in the same location from when you added it to your iTunes library. For example, if you added a song from a removable hard drive or a flash drive, then you unplugged or removed that drive from your computer then iTunes has no way of reading that file anymore. another example would be if you added a song from My Music in My Documents, and then for whatever reason either deleted that file or folder, or possibly moved it to another location, such as your Desktop, or in a Network folder. Basically, iTunes looks for the file wherever it exactly was when you added it to your library. if it is no longer in that exact location, it will not be able to find it. even if it is still somewhere within your computer