For most projects, some introductory or background information about the country's legal system will be essential. The following online and print sources include or can lead you to overviews of foreign legal systems.
To find books at USF that deal with a country's legal system, use Ignacio
Model your Ignacio searches on these examples:
law "country name"
"legal research" "country name"
For example:
law japan
"legal research" china
Use WorldCat Advanced Search to search worldwide for book-length discussions of a country's legal system.
In WorldCat, try "Subject" searches along these lines:
law -- "country name"
"legal research" "country name"
For example:
law -- japan
"legal research" china