Moving Music from WMP to iTunes sorted by Album

Greetings, I'm new here and about to dip my toe into the Apple pond for the first time. Just placed an order for an i Phone and am preparing my music collection to move at least some of it over to i Tunes for use with the new phone. I currently have it on an external HD in one main folder (CD Collection) and have been using WMP up to now. Stored under that main folder are sub-folders with album titles containing the individual song files in .wav format. I tried to import the files into the i Tunes library by going to FILE and clicking on ADD FOLDER TO LIBRARY. I then selected all the album folders and hit enter. It imported them all into one folder. I have around 450 albums. This is not what I had in mind. I had hoped the folder and file organization would have been maintained. Instead I have thousands of music files in one "album."

I guess I can just delete the "album" but is there any easy way to get all the albums over to i Tunes sorted into their respective albums with artwork etc (the artwork is available for WMP already)?

Any help with this would be greatly appreciated!

GL