Thanks to the Law Librarian Blog for linking to the ABA’s search engine for online law reviews, repositories such as SSRN and bepress, and Congressional Research Service reports. The search page also provides urls for the 300+ online sources covered, plus another 30 or so online journals to search manually. Note the caveat: search engine coverage varies; law libraries and fee-based services (LexisNexis, Westlaw, etc.) provide more complete coverage.