Hello Evelyn, consider this:
Go to gamsat-prep.com, sign up for a free account. When you login, click on Tests in the top Menu, scroll down and you will have a free sample GAMSAT with, of course, Section 1 (abbreviated version with free worked solutions). Try it, if you think that it is realistic (after all, you just tried some ACER questions so your own opinion would be quite valid) then you would have some options: (1) there are 5 more tests available online (full-length versions) and all come with worked solutions and a forum thread for each of the more than 900 MCQs for further clarifications or discussion of strategies if needed (no extra charge); and/or (2) there is a program called GAMSAT University which comes with 16 mini-tests to focus on graphs & tables, poetry, cartoons and verbal reasoning.
Frankly, if you are looking for realistic practice, there is ACER, the material that I described above and Des O'neill. Some students use Examkrackers Verbal but it is an MCAT book and though it may help to some degree, it's certainly not as specific as what I've mentioned above.
I'm sure you can see from my signature that I have a certain bias but as mentioned you can test out the free trial exam yourself to determine its usefulness.
btw, if it was months before the exam, then I would have also suggested some other free resources:
www.gamsat-prep.com/GAMSAT-Free
Good luck!
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Helpful links:
GAMSAT courses: Aust/IRL/UK
GAMSAT Preparation study materials
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