Smart Turn has recently published a free ebook titled "Inventory and Warehouse Management Best Practices". I am not usually in favor of such docs because they have marketing look and feel but this one is an exception and I liked the content.

One of the thing which I liked in the book was its structure: Every chapter starts with an overview of the subject complemented by three extra items:

Tips: These are specific tasks and Ideas which should be taken into account when implementing WMS or Inventory Management systems.

Notes: These are general observations on the improvement areas within the processes

ROI Benefits: These are the strategies which make you able to reap tangible benefits.

The book covers several topics like warehouse safety, slotting, RF use and collaboration in a logical order. I recommend you to take a look (The link is here).