Nice site--I downloaded a few papers for my dissertation literature review (my APSA paper is uploaded there, as well). As far as I can tell, you don't need to register to search for and download works. I also haven't tried any of the additional research links on the left-hand frame:
"The SSRN eLibrary consists of two parts: an Abstract Database containing abstracts on over 356,400 scholarly working papers and forthcoming papers and an Electronic Paper Collection currently containing over 290,700 downloadable full text documents in Adobe Acrobat pdf format. The eLibrary also includes the research papers of a number of Fee Based Partner Publications.
The Networks encourage readers to communicate directly with authors and other subscribers concerning their own and others' research. To facilitate this we publish detailed author contact information including email addresses for authors of each paper. We also provide electronic delivery of the papers when authors wish us to do so from the SSRN eLibrary."
Continued at SSRN
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