As I mention in the Introduction, the lyrics on this website were transcribed from vintage audio recordings, not published sheet music.
I can, however, offer a few general hints:
For most of these numbers, sheet music was published at the
time. Some are certainly more common than others. Some
of the more popular numbers are still commercially availible;
others have been out of print for decades.
Your first step should be contacting a music store to see if
they can order it.
If it's out of print, you might see if any libraries or music schools near you have collections of old sheet music which might contain that.
You might find a few usefull clues poking around some of the
sites connected to my Links
page.
If looking for titles on the web, try typing the title or a key phrase (in quotation marks) in a web search-engine, like Google or Yahoo.
If all else fails, try contacting the Library of Congress in Washington DC (repository of USA copyrights) to see about ordering a photocopy.
Happy hunting!
Cheers,