All audio CDs are currently shelved in the READ Japanese collection on the 22nd floor in the East Asian Reference Reading Room.
Use Advanced Search in the Library Catalog. Language=Japanese Format=Spoken Word
Here are some examples:
Dictionaries and Grammars are available in the East Asian Reference Room on the 22nd floor. There are also older dictionaries and extra copies of dictionaries in the stacks (some on the 8th floor and some on the 21st floor).