The Blume Library offers access to resources that review tests & measures. The Mental Measurements Yearbook and PsycINFO are sources for reviews. The PsycINFO video, below, gives you tips for finding articles with tests or reviews of tests.
The Library does not have a collection of tests or access to PsycTESTS. So, it is likely you will have to either 1) contact the publisher and purchase the test or 2) contact the author for permission to use the instrument. This method may be the only way to use "unpublished" test.
This box links to some sources of data. Most of these are freely available.
The Blume Library also has the following data source in print.
The Library does not have subscriptions to these products right now. But, The ICPSR includes some freely-available data.