The below information is outdated.Here is the St. Louis Obituary Index at the St. Louis Public Library website. It covers obituaries that appeared in the St. Louis Post Dispatch 1880-1927, 1942-1945, 1992-2006. Each year is divided into three separate lists alphabetically. If you know what year someone died, it's very easy to look up the date of their obituary (or burial permit) if it appeared in the newspaper. (The library has an index for The St. Louis Argus as well, organized in the same fashion). However, if you don't know the date, most people will find themselves looking in every year's list for their surnames.
Please follow this link for more recent info.
After a certain point, it is probably likely that any organization that is indexing a project that large will ask themselves...wouldn't a searchable database be easier to use? And their new Obituary Search is definitely easy to use. (I just discovered it this week, and so far they've entered the data for the Post Dispatch, 1880-1925 and 1942-1945.) You can search by surname, first name, or initials, though only the first 100 results are listed.
It will be somewhat sad, though, to see the indexes disappear, as I suspect they will, once they are done catching up in the years entered into the database. Because there is one advantage of indexed lists over databases. They show up in Google search queries. You have to know the databases are there in order to search them.
Still, I'm not complaining. The database is an improvement. And I am definitely happy the staff at the library is taking the time to make the information available online.