Legal Systems in ASEAN (open access) - from the ASEAN Law Association. Note that only 7 countries are so far included (not Cambodia, Lao PDR or Myanmar). For each jurisdiction, there are chapters on: Historical Overview, Sources of Law, Government and the State, Legal Procedure and The Legal Profession.
Juriglobe is a free resource produced by the University of Ottawa that helps you determine a country's legal system classification and related information. It also contains general information about the different legal systems and information on demographic distribution, world Gross Domestic Product (GDP), international trade and official languages.
The CIA World Factbook contains facts and figures on 200+ countries. It provides information on the legal system of countries, as well as the history, people, government, economy, energy, geography, communications, transportation, military and transnational issues.
WorldLII The World Legal Information Institute's research database, contains material on a large range of jurisdictions. WorldLII is a free, independent and non-profit global legal research facility developed collaboratively by a number of Legal Information Institutes and Law Faculties around the world. AustLII is one of the collaborating parties in WorldLII. You can browse by country, database, or region.
Globalex New York University School of Law's contains a foreign law research collection with chapters on over 150 countries. The guides are written by expert law librarians from each jurisdiction and include information about the legal system and links to free sources of law (if available).
Library of Congress Law Library The United States Library of Congress Law Library has produced guides to online legal research for a variety of nations. These highlight the primary sources for a range of jurisdictions, and where to find them online (if possible). The Library of Congress also has Foreign Law Research Guides for a selection of countries.