How to keep up with a voracious reader without pre-reading

How do you keep up with a voracious reader without pre-reading all the books? 

Liam is nine years old and an insatiable reader, and it would be impossible to pre-read every book I hand to him. At this stage, I've become his personal "book concierge," researching and recommending all the best books. He generally reads a chapter book a day, so it's quite a job. 
My secret weapon?
Quality book lists—and specifically, these two books:
Honey for a Child's Heart by Gladys Hunt
Books Children Love by Elizabeth Wilson
These books are true gold mines, brimming with time-tested, wholesome literature recommendations for a variety of ages and from several genres. Between these two books, our family has read hundreds of titles—enough to make me feel comfortable handing Liam a book from these lists that I've never read. 
Each of these books gives a short summary of the books they recommend and why they're recommended, so I can quickly glance through and make a list for Liam. If a book is listed, it's one I trust. Most of these books were written in a past era, one that was mostly free of slipping political agendas into children's books (how refreshing!). 
I use these lists for our younger children, too. It's how we've discovered some of our favorite beginning readers, classic picture books, and first chapter books. Reading through these lists is also how I found my favorite authors. So now when I come across a book by Elizabeth Enright or Eleanor Estes or Meindert DeJong or E. B. White (or a host of others), I know it's probably worth our time. 
Once I find a book I'm interested in, I look for it first at our library. If our library doesn't carry it, I visit to find it gently used. If I still can't find it on Better World Books, I look on Amazon. 
There are occasions when someone recommends a book outside these lists and I want a quick review. My go-to sources for reviews are and If it's not available on one of those sites, I go to Amazon and look for the 1-star reviews (because parents are good at chiming in when there's disturbing material). If I feel uneasy about a book, can't find a thorough review, and don't have time to pre-read it, I won't hand it to my son. There are too many other options!
I hope these books help your families as they have mine!