Hi LC,
Nova's book 'Master the LSAT' is highly recommended by many people. I bought that and also "the LSAT advantage with Professor Dave" because its ranking in Amazon is one of the best books. I also got some of the prep guides available for sale on the internet.
Just avoid the ones like Barron, Real which most people claim aren't helpful and explore as many books as $ and time permit because some materials offer insights that are unique to that book.
Good luck