ID3 Tagging

Ok, I am interested in doing something about my 30000+ item music collection. There are almost certainly duplicates and very certainly misidentified items. There are quite a few products in this area:

My main issue with these are:

I would also like to be able to examine large numbers of files and find the ones that don't exist in my collection already.


I envision a program that will definitely be difficult to pull off, but which I think is attainable: