Public Libraries (by holdings size) 

مواقع بحث خاصة بالمكتبات العامة  الأمريكية  حسب موجوداتها

Cal State Library -Sunsite, librarians' index of the web 
New York Public Library -Over 11 million volumes. 
Chicago Public Library -9+MM 
Queens Borough Public Library -8+MM 
Cincinnati & Hamilton County PL of -8+MM 
County of Los Angeles Public Library -7+MM 
Philadelphia Free Library -7+MM 
Pittsburgh Carnegie Library -6+MM 
Brooklyn Public Library -6+MM 
Los Angeles Public Library -5+MM 
Houston Public Library -5+MM 
Miami-Dade Public Library System -3.5+MM 
Hawaii State Public Library System -3.5+MM 
St. Louis County Library -3MM 
Dallas Public Library -2.5+MM 
Detroit Public Library -2.5+MM 
Jacksonville Public Library -2.5+MM
Baltimore Enoch Pratt Free Library -2.5+MM 
Orange County Public Library -2.5+MM 
Montgomery County MD Dept. of PL -2.5+MM 
San Diego Public Library -2.5MM 
San Francisco Public Library -2.5MM 
Fairfax County Public Library -2+MM 
Columbus Metropolitan Library -2+MM 
Atlanta-Fulton Public Library -2MM 
Phoenix Public Library -1.5+MM 
Kansas City Public Library -

University Libraries مواقع بحث خاصة بالمكتبات الجامعية الأمريكية

Brown University Library - 
Columbia University Library - 
Cornell University Library - 
Dartmouth College Library - 
Harvard University Library  -
MIT Library - 
Princeton University Library - 
Stanford University Library - 
University of Chicago Library - 
University of Pennsylvania Library - 
Yale University Library

Library Search engines   مواقع بحث خاصة بالمكتبات في العالم ومجوداتها

LibDex -Searchable database of world libraries - very comprehensive!

Federal Libraries   مواقع بحث خاصة بالمكتبات الفدرالية