For your science subjects, Checkpoints (not a study guide strictly speaking) is a good resource for doing those practice questions. There are notes at the back of them though, but not as good as those in a study guide like the "Notes" series.
However, the maths checkpoints are not as good value, because they simply mix and match questions from past official exams. Might as well do them yourself.
The reason why the university's official sites don't post definite clearly-in ENTERs ie because there, technically, isnt one. They use a Range of Criteria (RC) to determine entry. But, I can assure you, getting 99+ as an ENTER is an important first step, particularly for Melbourne and Monash but I dont know about other unis though.
Your performance on the UMAT (Undergraduate Medicine and Health Sciences Admission Test), I think is the other main criteria for medical courses. I personally havent done it, but there are some around here who have. It's important enough that if you dont even do this test, you have no chance of getting into most medical courses. That said, monash paramedic doesnt need umat.
going by reputation alone, Vet science is notoriously hard to get into, even harder than normal medicine, while Paramedic, I think is RELATIVELY easy.