Laura K. Justiss of the SMU Dedman School of Law has posted an interesting article on SSRN titled A Survey of Electronic Research Alternatives to Lexis and Westlaw in Law Firms (including a link to the downloadable 33 page pdf). The User Education in Law Librarianship blog has posted more information about the article, pointing out several useful tables in which she compares alternative resources and their usage in law firms.
From the abstract: "Justiss conducted a survey of law firm librarians in 2010 that identified electronic research database alternatives to Lexis and Westlaw and ranked them by subscription frequency. The survey included research databases for primary source alternatives; court docket and case information services; secondary sources for topical legal research and legal periodicals; financial, business and news sources; public records; and non-legal and legal-related sources, including intellectual property databases. The survey also generated information regarding suggested or mandated legal research policies in law firms for the use of alternatives to Lexis and Westlaw and examined their applicability to billable and non-billable research. Lastly, it examined the prevalence in firms of flat rate pricing agreements with Lexis, Westlaw or both. "