Hi! I’m looking to self study for the SSAT but need some suggestions on books that offer practice. I’d like to focus on mathematics, but really just need to find good/plentiful practice and information to understand the test. So far, I have the official guide and “Cracking the SSAT”. If you have any suggestions, that would be great. Thank you! 
Princeton review for the sat and isee is a very good book that I used to help me study
I really like the Barron’s book because it explains why answers are right.
I know that you said math, but be sure to also study vocab - it helps in multiple sections and is easy to study. There are lots of SSAT vocabulary study lists on Quizlet.
The question packet in the official SSAT website really helps as well. Although the price is quite expensive compared to other books, it is definitely worth it!