Free clerical tests can be taken online at one of many websites such as Aptitude-test.com and LoveToKnow. Smaller quizzes can be found at Amby.com and ProProfs.
Aptitude-test.com offers a four-part clerical test with sections on alphabetical and numerical filing, attention to detail, workload and concentration, and data checking. LoveToKnow's seven-part test includes proofreading, math, typing, online computer skills and using clerical skills.
Both the tests and the quizzes utilize PDFs, online forms and Flash players, so it is important to make sure that this software is updated before taking the tests. Each test also includes immediate answer checking or an answer key.