One of the fantastic benefits of the Internet is that so many cases and codes are available online for free. Here are some links for you to bookmark. Why so many that overlap? They differ in coverage, ease of use, ease of searching, formatting, and so on. As you try each, you will get to know what works best for you.
One [huge] caveat: Shephardizing (or the ability to Keycite) is NOT available for free on the Web. And we can extend this warning: there are new developments in laws that can’t even be found by Shephardizing. For example, sometimes states pass laws that vitiate previously existing statutory or case law, but do not refer to the statutes or cases they are repealing. It helps to do a news search on the subject matter just to make sure!
Cornell Legal Institute is a portal for just about everything you could want, including cases, statutes, U.C.C., C.F.R., Table of Popular Names (especially helpful when checking newspapers and other resources for changes in laws!) and so on. I prefer it because of its great formatting and ease of use.
Google Scholar’s court opinion coverage is limited to state appellate and supreme courts from 1950; federal district, appellate, tax and bankruptcy courts from 1923; and the U.S. Supreme Court from 1791. In a useful feature, cases are sorted by the extent to which they have been discussed in citations. See Google’s explanation here.
Also, Google Books contains many compendia of case law, some of which contain scanned transcripts of old cases you can’t find anywhere else. If you search for the specific case in Google Books, you can often flush out the relevant compendium and access the case.
Library of Congress Database for Statutes and Bills (Congress.gov was formerly known as Thomas.)
Electronic Code of Federal Regulations (unofficial editorial compilation of CFR material and Federal Register amendments kept very current)
Includes proposed regulations
Updates for state statutes
Hot legal issue links
List of links of where to find them
Statutes at Large
Oh, you know you don’t want to root through all of that yourself! Get some help! Here is a link to free legislative histories on the Web!
Special Focus: Native American Law
The Meaning of It All
Finally, when nothing else will do, the whole (free) Blackstone’s Commentaries, here.