A very rough and unscientific tiered ranking of Economics Ph.D. programs 
drawn from various rankings and reputations.  The ordering within each tier 
is even more subjective.  The top 6 would appear in any reasonable top 10 list; 
the top 10 would appear in any reasonable top 15 list; the top 17 would appear 
in any reasonable top 20 list; the top 24 would appear in any reasonable top 30 
list.  Then things get a lot harder to rank!

U. of Chicago
Harvard U.
MIT
Yale
Princeton
Stanford

U. of Pennsylvania
Northwestern U.
U. of Wisconsin
U. of California - Berkeley

U. of Minnesota
U. of Michigan
Columbia U.
NYU
U. of Rochester
UCLA
U. of California - San Diego (Economic Theory, Econometric Theory)

Cornell
Carnegie-Mellon
Johns Hopkins
Boston U.
Penn State
Brown
Cal Tech (Economic Theory)

Arizona State U. (Macroeconomics)
Washington University
U. of Texas
Duke
U. of North Carolina
U. of Maryland
U. of Washington

Ohio State
U. of Illinois
U. of Pittsburgh
U. of Iowa
Iowa State
Boston College
U. of California - Davis
Michigan State U.