First I just explored a variety of Categories and posted above link to an article I "stumbled upon" and found interesting.
Then for my actual Discovery Exercise using search engine tools to find a site that would have applications for use in a library setting, I chose the Category "Books".
"Lulu" was the 1st place winner, but I found it to be too commercial a site since I already use and am familiar with Amazon.
The 2nd Place winner was "Biblio" which is for used or rare books so I could refer customers to it.
The 3rd place winner was "VuFind", a resource portal software for Academic libraries developed by Villanova University of PA. The goal of VuFind is to enable users to search and browse thought library resources by replacing the traditional OPAC. Many major Universities are using or testing.
"Worldcat" and "LibraryThing" received Honorable Mention Awards. I learned that Worldcat is becoming more and more accesible to the general public, and while I was again exploring "LibraryThing" (Thing #11), I added another title to my book list.