I recommend reading this after Pale Demon to avoid spoilers. The ending of this book is just after the time frame of Pale Demon. I also suggest that if you are planning to do a reread of the Hollows series that you read this prior. The Hollows insider has a very in-depth look at the species in the series. Also a few tidbits on storyline that would make you go "Ah ha" while rereading the series. 
 Also, I don't know if a ebook format is available but I would suggest against it. To truly enjoy this book you need it in hardcover. It reminds me of a text or a reference book. A large hard cover book that seems to be heavier the appearance suggests. It basically is the file that the Journalist Devin has amassed during the time frame of the entire series. 
 Some of my favorites in the book: 
 ~Jenks list of favorite swear word phrases most pertaining to Tink. *Tink's a Disney whore* My all time favorite! 
 ~The Copy of Witch's Weekly! *Everything in the issue* Jenks 12 days of x-mas and Rachel's anonymous poem of the night before Christmas. 10 ways to tell your roommate uses black magic. Ryn Cormell's "how to date a vampire" guide. It was all priceless! 
 ~The Brimstone cookie recipe 
 ~Every article that Devin has published in the paper and most important his final one. 
 ~Devin's reimbursement of expenses. Love the Boss' commentary on his need for anti-itch cream. I noticed that his final bill was tallied to include all the times he was denied the reimbursement! Loved it! 
 ~ A tear may have escaped when I saw Kisten's obituary. :( RIP Kist, We miss you <3 
 Most important! You see just how much work Trent has put out to keep Rachel's ass out of hot water. The man was running around cleaning up her messes and we never knew it. I wonder if he was amused as she tried to get him arrested time after time. I've loved Trent since book 1 when we only saw his as the villain. But then again any who have read my reviews know how much I love the villain! 
 Kim Harrison put a lot of work into this guide. Extremely in-depth and informative! I am hungering for a reread of the series now! I miss Rach&Friends. I can't wait for the next installment to pick up where Pale Demon left off. This insiders guide extended my patience for the next book while simultaneously wetting my appetite for a reread!