When you find a good book - look around the shelves in that area for more. You are guaranteed to find something browsing you miss keyword searching the catalog. Explore tables of contents and indexes in books that catch your eye
Try these approaches to library catalog searching
Texts in translation published as books are your key primary sources.
Look up primary sources mentioned in the footnotes and bibliographies of your secondary sources and reference books
Recent studies in scholarly journals will cite the most current translations of primary sources
If there is a work cited in a language you don't read, search WorldCat by author for a recent translation (then use ILL)
If Vassar library doesn't have the book you need, use WorldCat to request something through ILLiad