Hi, Harpy - that's a problem at the American Memory Collection, and Levy is almost as bad. If you try to link to the actual sheet music, you come up with an URL that's a yard long, and it doesn't always work. I've found you often have to print out the sheet music to read it.
Good luck.
This link (click) might be a bit easier. Take a look through the Index (click), though - there's some great sheet music there.
-Joe Offer-