Unpublished tests that have not been commercially published can often be found in books. Below is a list of books in the Pfau Library where you can find tests and measures full-text. You can photocopy or scan the tests inside.
When you get the book, check the Table of Contents, Lists of Assessments, Index, and even at the end of the chapters to locate the test.
A few wonderful people have thought to assemble online lists of books that have complete measures in them. Once you get used to the layout and format, these home-grown catalogs are treasure troves.