It sounds to me like you haven't added them to your iTunes Music Library for a start. The LW song list in iTunes is simply a playlist & the songs still reside in your downld folder. More on this here: How to transfer music to my iPod (& iTunes)

Within iTunes you can select the song use control & i command (apple & i keys for mac) to bring up id3 tag info. You can select ones by the same artist or album by selecting multiples at once using the SHIFT key as you select. I do this all the time & is much faster than doing them individually.