Local law frequently is referred to as "municipal law" because municipalities (also called municipal corporations) pass much local law. Other local entities, such as counties, also can pass laws, however.
Most states are Dillon's Rule states, which means that local governments derive their powers from the state and only can exercise powers that the state specifically authorizes them to use. In these states, some localities may be "home rule." This term refers to local jurisdictions that have an extra degree of authority to create laws or otherwise deal with local issues, so long as they operate within state law. A minority of states are home rule states, where the state constitution allows localities to govern themselves as they wish, provided they are in accordance with state and federal constitutions. A few states have a hybrid structure.
Local-level statutes typically are called ordinances, and their published compilations are called codes. Home rule municipalities often also have a Home Rule Charter, which can be likened to a constitution for the municipality.
Many local governments have three branches: legislative (such as council or commission), executive (such as a mayor, agencies, and/or departments), and judicial (such as district or municipal courts with limited jurisdiction). Local government websites often contain a wealth of information about the county or municipality, such as codes, forms, and how-tos, as well as contact information for government offices and officials. Phone calls may get a better response than an email.
In addition to the local government's website, local codes may be found on one of several websites. (Tip: An internet search for "[municipality name] code" or "[municipality name] ordinances" often is the best bet for finding them.) Local code databases include Municode, General Code: eCode360, and American Legal Publishing. Codes may be drafted by the local government or may be based on model codes.
Local newspapers contain coverage of local government activities, including law-making, that may provide insight into why an ordinance was passed and how it has been implemented. Local newspaper coverage is available via Lexis News (Temple Law access) or Temple University's various newspaper databases (Temple University access).
The best bet for locating municipal court opinions is the court's website. Historical opinions sometimes may be found in reporters compiling a state or region's local court opinions. These reporters many be available in print or in databases such as HeinOnline's State Reports: A Historical Archive. Libguides on a specific state's local law may point you to additional resources.