Reddit mentions of 5 lb. Book of GRE Practice Problems: 1,800+ Practice Problems in Book and Online (Manhattan Prep 5 lb Series)

One additional consideration: as confirmed by their product descriptions, buying any of the 4th edition books gives you access to Manhattan Prep's 6 online practice GRE tests. The product descriptions of the new 5th edition books make no such promises. Manhattan sells the 6 practice tests for US $50; if you want both the books and the practice tests, it's cheaper to just buy the 4th edition books new on Amazon (while they last) and get the practice tests included for free.

Side note for anyone interested: I just saw that a new edition of the 5lb Book will be released on December 4th as well, and it's up for preorder on Amazon now. According to its description, the new edition "has been updated to include an online companion of lessons from Interact® for GRE, our revolutionary interactive, on-demand learning platform. In addition, the book now includes new mixed timed sets, a cheat sheet of key math rules, and micro drills to test individual skills." Link: https://www.amazon.com/gp/product/1506247598/

This is the one I used: https://www.amazon.com/gp/product/1506247598/ref=dbs_a_def_rwt_bibl_vppi_i0

I'm currently using ETS material for all the verbal, but for non-ETS material. I use the 5-lb Book of GRE Practice Problems from Manhattan Prep (https://www.amazon.com/lb-Book-GRE-Practice-Problems/dp/1506247598/ref=sr_1_1_sspa?keywords=gre&qid=1559187676&s=gateway&sr=8-1-spons&psc=1).

I got it on sale last December alongside with the GRE vocabulary flashcards.

However, my friend swears by Magoosh. I didn't want to drop $149 when I'm taking the exam in 3 months. I suggest utilizing and exhausting all of the free resource before thinking about buying GRE prep courses.