The Education Resources Information Center, or ERIC contains many tests, measures and scales.
There are two suggested tips for searching ERIC for tests and measures.
First, you can put a subject keyword in the search box and in the "Options" select Tests/Questionnaires in the Publication Type option.
The other option, is to enter your subject keyword and then in the box below put in the term append* (note the asterisk). The database will then retrieve different endings such as append, appendix, and appended. Ariticles with appended tests will then be easily located.