Why did 100+ Tracks not make it to their proper folder during transfer?

I moved from a PC to a Macbook Pro recently.

I followed the instructions to move my itunes library over using an external hd.

All was good. MOST made it, not all, which is kind of annoying. And when I go into some albums, many tracks are missing. WHERE'D THEY GO??

I scroll down to the bottom of my albums and lo and behold.....there are about 200+ tracks just sitting there, no names, no artists, just the track name.

I'd REALLY prefer not to take the time to place all of these tracks, figure out the artist, the album, etc.

Any help would be cool. Thanks.