Inomics

Karl-Heinz Brodbeck
Nouriel Roubini
Alan Deardorff's glossary of international economics
Paul Krugman
Hal Varian

CESifo, Universität München
CEPR, Centre of Economic Policy Research, London
EPRU, Economic Policy Research Unit, University of Copenhagen
FEEM, Fondazione ENI Enrico Mattei, Milano
NBER, National Bureau of Economic Research, Cambridge, Mass.
SSRN, Social Sciences Research Network

DIW Berlin
HWWA Hamburg
IfW Kiel
IW Köln
IWH Halle
RWI Essen
ZEW Mannheim
Sachverständigenrat (Council of Economic Advisors)

Beijer Institute of Ecological Economics, Stockholm
IIASA, International Institute of Applied Systems Analysis, Laxenburg
Max-Planck Institute for Demographic Research, Rostock
WZB, Science Center Berlin

Universitätsbibliothek Rostock
EconLib, Library of Economics and Liberty (Books by Smith, Ricardo, and others, new edition)
Kiel Institute of World Economics library (very good catalog, continue with: ECONIS)
NBER discussion papers

American Economic Association
European Economic Association 
Royal Economic Society
Verein für Socialpolitik (German Economics Association)

Thünen-Gesellschaft