I played hookey from work today and was able to work on my music library. I copied and pasted all my music from all the computers on to an external hard drive. I plugged the hard drive into my laptop because it is the newest computer I have. Then created a new folder "all music". I used the Vista search feature with *.*mp3. It came up with over 5,000 results, many are the same copies. I did the select all, cut and then paste into the new folder. It took about an hour but, much to my surprise, Vista did not choke on this large task.
It sorted through all the songs and did not copy the same file twice. I did the same with m4p and WMA files and ended up with about 2,700 songs. (I found something nice to say about Vista. I bet XP would have locked up)
Then I cleared out itunes and imported my new folder. I asked it to show duplicates and deleted the ones I didn't want. As I went through them one at a time adding to my playlists, I then weeded out the ringtones etc. leaving 2,177 tracks. To the best I can tell, I am not missing anything. I am now syncing the ipod. Things are good again!