Sometimes (actually quite often) I harness the power of Google Books to get me to the titles of books that I need. Because Google can drill deep into the actual content, rather than just the words of the titles or the tables of contents, it saves me hours of time that I used to spend flipping through books that I thought might just be useful. So, used in conjunction with the physcial texts in the library you should be able to find all kinds of materials for your research.
Remember to search carefully and thoughtfully. Use boolean (AND OR NOT) searching to help limit the results.
These days most search engines (and the library catalog is a search engine) default to keyword searching. There is no doubt that keyword searching can be very helpful because it drills deep down into words in tables of contents when they are included in the catalog records. But it can also be limiting if the authors of the books did not use those exact terms. For instance, a keyword search on "queer japan" retrieves only 19 entries and when you look at them some are spot on but others pull the term queer from one article and Japan from another article in the same book. And, did you find everything we have?
Subject headings are another way to locate materials. Subject headings are assigned by librarians according to a controlled vocabulary established by the Library of Congress. Any materials written about "Queer Japan" would have been assigned the subject heading: Homosexuals -- Japan until the late 1980s, when it changed to Gays -- Japan or Gay men -- Japan. Because the library catalog uses controlled vocabulary, all the old records that used Homosexuals -- Japan have been converted to Gays -- Japan.
There also narrower subject headings: Gay men -- Japan and Lesbians -- Japan You won't find many entries, but there may also be: Gay men's writings, Japanese Sometimes you may want to look at broader entries such as: Gay men in literature and Gay men in film
You will still find books that use the subject heading Homosexuality to represent scholarly works using a sociological and/or psychiatric approach.