Statutes, regulations, insurance department opinions, and other primary materials for all 50 states are compiled in print in the multi-volume National Insurance Law Service (NILS) and online via NILS INsource. Otherwise, you can also get statutes, administrative codes, etc. from free government web sites, Lexis and, Westlaw, and the various low-cost legal information providers (see "State Statutes," "State Cases," etc.). The National Association of Insurance Commissioners (NAIC) posts a map linking to the state insurance departments' websites.
The leading insurance law treatises are Appleman's Insurance law and practice (LexisNexis) and Couch on Insurance (West). Appleman is available on Lexis (INSURE;APLMAN). Couch is available on Westlaw (COUCH). I have been told that Liability Insurance in International Arbitration (Hart Publishing) is the only book on the topic.
There are some useful full-text secondary source materials on Lexis and Westlaw, notably materials by the National Association of Insurance Commissioners (NAIC) and law review articles. To find insurance-related articles, search Westlaw's INSNEWS database or the appropriate files in the Lexis INSURE library. Alternatively, if you have access, you can search the Insurance Periodicals Index on EBSCOhost.
Lexis has the full line of Mealey's insurance news and pleadings databases, as well as NAIC materials (INSURE;MODLAW) and a substantial number of insurance treatises. Click here for a list of the available treatises, or here for a list of insurance-related Mealey's databases.
The Davis Library at the School for Risk Management, Insurance and Actuarial Science (formerly the College of Insurance) in New York City is an excellent source for insurance-related materials. They do research and document delivery for students, faculty and members of the Insurance Society of New York; non-members can use the library only by coming in person and purchasing a pass, but their online catalog can be used to identifying insurance-related materials. For more information, visit the Davis Library web site or call 212-277-5135.
Automobile Insurance: State insurance laws and regulations are summarized at length in Automobile Insurance Laws, published by the American Insurance Association. Abbreviated summaries are published in The Lawyer's Almanac. See also "Automobiles" and "Driving."
Annotated Insurance Policies: Probably the best source for case law interpreting insurance policies is Miller's Standard Insurance Policies Annotated (West). Miller's is available in print as a multi-volume looseleaf service and electronically through and Westlaw (MILLERS-ANN). If Miller's doesn't address your topic, search an appropriate case law database (see "State Cases").
Claims Search: Attorneys litigating automobile accidents and other personal injury suits will often want to know whether the other party is one of those people who files loads of insurance claims. A company called ISO sells this information, either on a case-by-case bases or through a database called ISOClaimsSearch.
50-State Surveys: The Compendium of State Laws on Insurance Topics summarizes the laws and regulations on a wide range of insurance-related topics(see the "National Association of Insurance Commissioners" entry for more about the Compendium). Lexis offers a database of insurance-related 50-state surveys (INSURE;STSURV). Westlaw offers the Oden state statute and regulation summaries as an equivalent (ODEN-SUMMARIES).
Foreign Insurance Laws: The MULTI-INSF database on Westlaw database includes insurance statutes, regs, and other primary legal materials not only from the U.S. but also from Bermuda, the Cayman Islands, Guam, Puerto Rico and the Virgin Islands. For more information, see "Foreign Laws."
Policy Forms: ISO Policy forms are available by subscription to the ISO Forms Library or on a per-search basis on Lexis (INSURE;ISOFOR). Common insurance forms are included in Miller's Standard Insurance Policies Annotated (West).