A very useful page and worth bookmarking..
They write by way of introduction:
Free & Low Cost Legal Research
Introduction
The major legal research databases can be prohibitively expensive for some researchers. There are, however, a number of online alternatives that are either free or less expensive than Lexis/Nexis and Westlaw.
The first part of this guide provides an overview and links to different types of free materials and the second part summarizes the features and costs of less expensive databases.
Free Sources of Legal Materials
There are several databases which provide access to primary source materials on their own sites, without any charge to the user. These sites vary in terms of the types of materials collected, the scope of their coverage, and their search options. We have created a table for each type of material which includes the major online sources and their coverage.
Because the availability of state legal materials varies so widely, we have only included descriptions of the federal materials available for free online. Please consult our state research guides for information about individual states.
Case Law
There is an abundance of free case law available online. Unfortunately, many of the editorial enhancements and finding aids that legal researchers are accustomed to are not available through these free sources. For example, these sources do not provide digests or headnotes, which organize cases by points of law. Instead, these sources utilize browsing and keyword searching as the principal means of finding relevant cases. Researchers should be aware of these limitations and understand that keyword searching and browsing are not necessarily the best methods to find cases.
http://www.ll.georgetown.edu/guides/freelowcost.cfm
