Directories, indexes, and collected reviews of tests are listed here.
While Mental Measurements Yearbook (MMY) is typically the best first place to look, neither MMY nor any single source can truly be considered a comprehensive index to tests that may exist!
Tests are sometimes published in journal articles.
PsycINFO and ERIC are two databases that offer specialized search functions for locating tests within journal articles.
These are sources for identifying and selecting tests, including indexes, directories, and reviews.
Most of these are available in the Reference collection on the first floor.
Some of the handbooks are in the circulating collection on the 2nd floor.