Searching for books on Indigenous Law in the library catalogue is best done using the name of a First Nation, a geographic location, along with the terms land, law, legal etc. For example: Indigenous peoples--Legal status, laws,
Recently published books (monographs) on the Law of Indigenous Peoples in North America will now be found shelved in the following call number areas: KIA to KIX. Books on treaties are included in KI. KI does not include Canadian law relevant to Indigenous People, particularly the Indian Act, or materials published by Continuing Legal Education of British Columbia, RCAP, and historical publications by the Royal BC Museum and the Museum of Civilization.
KI - Law of Indigenous peoples in the Americas
KIA201- Indigenous Law: Arctic and Sub-arctic Regions - Northern Canada
KIB Indigenous Law : Canada General
KIC - Indigenous Law: Canada Eastern
KID - Indigenous Law Canada Western
KIE - Indigenous Law United States General
KIF United States Northeast Atlantic
KIG United States South
KIH United States North Central
KIJ - United States Pacific Northwest
KIK United States New Southwest
KIL - Indigenous Law Mexico
etc
https://www.loc.gov/catdir/cpso/KIA-intro.pdf