ALAIK the folder set up for iTunes Music Library depends upon the id3 tag. So if the song file has an incorrect id3 tag, you can correct it within iTunes itself. Just select the song within iTunes, Command & i keys or go to file menu>Get info (or mighty mouse users use front button depending on your configuration of it) & then change the incorrect details or add what's missing. After you've finished, iTunes will automatically update its music library & any incorrectly labelled artist/album will be put into a new folder or existing folder of that artist. Check it out. As Only A Hobo suggested, if you have iTunes preferences set so it arranges the library (tick option to Keep iTunes Music Library organised), then iTunes will do this all in real time if any details are changed.

Attempting to do it manually outside of iTunes will not work properly. I always double-check the id3 tag info to make sure all details are correct. Arrange songs by date added temporarily. I also use Media Rage (previously mp3 Rage) to check all details. Media Rage is a tagging program & any file not added to iTunes, I check/add the id3 tag info & update the tag version before adding to iTunes. This is handy for albumwrap files in particular.

__________________
Imagination is more important than knowledge. -- Albert Einstein
Only two things are infinite, the universe and human stupidity, and I'm not sure about the former. -- Albert Einstein
640 K [of computer memory] ought be enough for anybody. -- Bill Gates (1981)
The secret to creativity is knowing how to hide your sources. -- Albert Einstein
When facts don't fit the theory, change the facts. -- Albert Einstein
Religion keeps the poor from murdering the rich. -- Napoleon Bonaparte
The important thing is not to stop questioning. -- Albert Einstein
I know not with what weapons World War III will be fought, but World War IV will be fought with sticks and stones. -- Albert Einstein
"A composer is a guy who goes around forcing his will on unsuspecting air molecules, often with the assistance of unsuspecting musicians." -- Frank Zappa
"Tobacco is my favorite vegetable." / "May your sh*t come to life and kiss you on the face." / "Scientology, how about that? You hold on to the tin cans and then this guy asks you a bunch of questions, and if you pay enough money you get to join the master race. How's that for a religion?" / "Communism doesn't work because people like to own stuff." / "There are three things that smell of fish. One of them is fish. The other two are growing on you!" / "Jazz is not dead, it just smells funny." / "The creation and destruction of harmonic and 'statistical' tensions is essential to the maintenance of compositional drama. Any composition (or improvisation) which remains consonant and 'regular' throughout is, for me, equivalent to watching a movie with only 'good guys' in it, or eating cottage cheese." / "Remember there's a big difference between kneeling down and bending over." / "The most important thing to do in your life, is to not interfere with somebody else's life." / "Rock journalism is people who can't write, interviewing people who can't talk, in order to provide articles for people who can't read." -- Frank Zappa
"The music business is a cruel and shallow trench, a long plastic hallway where thieves and pimps run free and good men die like dogs. There's also a negative side." - Hunter S. Thompson
The shy can light the dull dark room with life when their eyes mirror their inner sunrise - LOTR