You can prefer the books to prepare for IPMAT is Crack the IIM Indore IPM Entrance Exam published by Pearson and written by IIM Lucknow Alumnus Nishit Sinha.

Along with this, you should also practice last year papers by setting the same time limit as it's going to happen in the final exam this will help you to prepare a proper strategy to give your maximum in the paper and also you will be able to recognise your strength and weakness.

Good Luck!