Before beginning to research the law in a foreign jurisdiction, it is important to know what legal system the country uses. Most English-speaking countries use the common law system, while most non-English speaking countries in Europe, South America, Asia, and Africa use the civil law system. The common law system depends on precedent set through case law, while civil law systems are centered around codified legislation.
British common law was the basis of law in most English-speaking jurisdictions, and still underpins many national legal systems to a significant degree. Some preliminary research in UK law may prove useful, particularly in Commonwealth nations where the British legal system may have been used exclusively for significant parts of the country's history. American and Canadian cases are also often cited persuasively in many English-speaking jurisdictions.
Remember that in civil jurisdictions, where judicial precedent has limited or no authority, cases are irregularly published. In all non-English speaking jurisdictions, codes and cases may not have been translated into English and the reliability of the translation may vary greatly.
The Law Library holds several foreign legal treatises, which can be found by searching the catalog or browsing the collection in the basement. We do not specialize in foreign law, however, so you may need to visit another library for detailed research.