We highly recommend that you begin your research by consulting a secondary source. Westlaw and Lexis both have immigration-specific secondary source collections that include materials like treatises, encyclopedias, law reviews, and forms.
AILALink is a comprehensive web-based library of primary and secondary immigration law materials, created by the American Immigration Lawyers Association. It includes the full text of Kurzban’s Immigration Law Sourcebook and many other books, as well as links to cases, statutes, regulations, forms and the newsletter Immigration Law Today.
Westlaw's Interpreter Releases and Interpreter Releases Daily provide regularly updated analysis of legislative, administrative, and judicial developments related to immigration law.
Bender's Immigration Bulletin, on Lexis, is a similarly helpful mix of news and analysis.
The following bibliography is helpful if you are looking for resources on a specific topic. Note that some of these materials may be out of date.