To find books, DVDs, maps, sound recordings, manuscripts, and much more - everything except articles - use a library catalog.
OskiCat = most UC Berkeley libraries
MELVYL = all UC campus libraries, including all UC Berkeley libraries
What's the difference? more details here
For each item make sure you know the name of the physical library, call number, and whether or not it's checked out, library use only, etc.
To find slang dictionaries, you can search OskiCat, for example:
(keywords): american slang dictionaries
english language slang dictionaries
if you're looking for older terminology, sort your search results by date and look for the older ones, such as:
Google Books contains millions of scanned books, from libraries and publishers worldwide. You can search the entire text of the books, view previews or "snippets" from books that are still in copyright, and read the full text of out-of-copyright (pre-1923) books. Want to read the entire text of an in-copyright book? Use Google Books' Find in a Library link to locate the book in a UC Berkeley library, or search OskiCat to see if UC Berkeley owns the book.
Why use Google Books?
Library catalogs (like OskiCat) don't search inside books; using a library catalog, you can search only information about the book (title, author, Library of Congress subject headings, etc.). Google Books will let you search inside books, which can be very useful for hard-to-find information. Try it now: