At my university usually all tests are published by the institutes themself on the iternet. They even advice you to train with the old exams. Some of them are also open book. But every exam is individual and so different (not only numbers changed) that you really have to train all the stuff to get a positive mark.
Relying on "secret" question caches or buying questions from a third party is not very smart, lazy and really makes no sense to me. They did´nt cracked the system, they only used it for their belongings.