I think you can do this with a redirect in your .htaccess file. I have never tried to go from a folder to a file, but the second one should work fine.
is the redirect
states that the file is moved permanently
is the file that people entered (do not use the full address for this)
is the page you want people to go to (must use full address)
Something like this perhaps:
Redirect 301 /Products http://www.yankgulchmusic.com/products.html
Redirect 301 /UnsungSongsDetails.html http://www.yankgulchmusic.com/DETAILSFILES/UnsungSongsDetails.html
If you google search "htaccess redirect" there are many sites on this. There are several ways to do things, depending on what you are trying to do.
Be careful using htaccess, as you can case problems very easily.