What is the order of the books?
The Prey books do take place in chronological order, although people seem to read them out of order. Similarly, the Kidd novels take place in a particular order, and people often start with the second novel because the paperback erroneously claims that it's first. The full list, by series, is:

The Prey series:
1. Rules of Prey (1989)
2. Shadow Prey (1990)
3. Eyes of Prey (1991)
4. Silent Prey (1992)
5. Winter Prey (1993)
6. Night Prey (1994)
7. Mind Prey (1995)
8. Sudden Prey (1996)
9. Secret Prey (1998)
10. Certain Prey (1999)
11. Easy Prey (2000)
12. Chosen Prey (2001)
13. Mortal Prey (2002)
14. Naked Prey (2003)
15. Hidden Prey (2004)
16. Broken Prey (2005)
17. Invisible Prey(2007)
18. Phantom Prey (2008)
19. Wicked Prey (2009)
20. Storm Prey (2010)
21. Buried Prey (2011)
22. Stolen Prey (2012)
23. Silken Prey (2013)
24. Field of Prey (2014)
25. Gathering Prey (2015)
26. Extreme Prey (2016)
27. Golden Prey (2017)
28. Twisted Prey (2018)
29. Neon Prey (2019)

The Virgil Flower series:
2. Heat Lightning (2008)
3. Rough Country (2009)
4. Bad Blood (2010)
5. Shock Wave (2011)
6. Mad River (2012)
7. Storm Front (2013)
8. Deadline (2014)
9. Escape Clause (2016)
10. Deep Freeze (2017)
11. Holy Ghost (2018)
12. Bloody Genius (2019)

The Kidd series:
1. The Fool's Run (1989)

The Singular Menace:
1. Uncaged (2014)
2. Outrage (2015)
2. Rampage (2016)

Non-Series Books:
Dead Watch (2006)
Saturn Run (2015)

What were the latest books to be released?
The most recent Prey novel was Neon Prey, in April of 20190. The most recent Virgil Flowers novel was Holy Ghost, on October 9th, 2018.

What's coming out next?
The next hardcover novel will be Bloody Genius, the twelfth novel in the Virgil Flowers series. It will be released on October 1, 2019. After that, Masked Prey, the thirtieth Prey novel, should be out in April of 2020.

What about the paperbacks?
The paperbacks typically come out not quite a year after a book comes out in hardcover. So if you see a new hardcover, that means that the previous one in that series is available in paperback.

I heard that John Sandford died recently. Is this true?
No. The rumor (probably) started when Lawrence Sanders died in 1997. Sanders wrote in a the same subset of thriller fiction as John Sandford, and the names were close enough that it caused some confusion.
Later, in 2005, Christian minister and author John A. Sanford died, and the rumors started again.
As of this writing (August, 2019), John Sandford is 75 years old and in good health.

Will there be any more Prey novels?
Yes. The 29th book in the series, Neon Prey was released April 23, 2019, and the thirtieth, Masked Prey, will be out in early 2020.

Will there be any more Virgil Flowers novels?
Yes. On October 1st, the twelfth Virgil Flowers novel, Bloody Genius, will be released in hardcover, audiobook, and ebook formats.

Will there be any more Kidd novels?
Possibly, but probably not. We've had ideas for a potential fifth book, but the truth is the Kidd series simply doesn't sell well enough to justify a new Kidd novel versus another Lucas or Virgil novel. If there ever is another novel in the series, it's going to have to be completely different from the previous ones.

Will there be any Night Crew novels?
Probably not.
The author thought for a while that he'd write a second Anna-and-company book at some point in "the future", but has since decided that Anna is basically a female Lucas, minus the badge. And having two characters that similar, by the same author, is just redundant.
Further, Los Angeles really isn't his area. He knows the Twin Cities and the surrounding countryside, but he just doesn't have the same rapport with the west coast. And one of his favorite authors, Robert Crais (who is, in turn, one of my dad's fans) does have that rapport with L.A. So my dad's leaving the west-coast stuff to him, although there's no formal agreement (and a formal agreement would be kinda weird anyway).

Are any of the books going to be made into movies?
Two already have been, sort of.
In 1998, Jaffe/Braunstein Films, Ltd. made a TV-movie of Mind Prey, starring Eriq LaSalle (Doctor Benton on E.R.) as Lucas Davenport. It got mediocre ratings, and fared poorly with fans.
In November of 2011, the USA TV network aired a TV movie of Certain Prey, starring Mark Harmon (of NCIS fame) as Lucas Davenport. The ratings were extremely strong, giving the USA network its highest numbers for the year, and ranking as the number-two first-run cable movie of the year. Reviews were decidedly mixed with fans and non-fans alike polarized.
The USA network has not announced plans for any more movies, and at this point it seems unlikely that they will.

Has he considered doing a crossover with [name of author]?
No. Writing is (usually) a solitary art. While authors occasionally collaborate with other authors, that remains the exception rather than the rule. Sometimes authors may mention Lucas or Lucas-like characters in their novels, and John Sandford frequently includes references to other authors and their characters, but there will not be any direct crossovers
He has, however, written two collaborations with his wife (and is working on a third): the young-adult sci-fi series The Singular Menace. He is also working on a stand-alone science fiction novel called Saturn Run with photographer and physicist Ctein.

Is John Sandford going to kill off Lucas someday?
The standard answer he gives for this is, "No, because my editor has told me that it would kill sales of the backstock."
This doesn't mean that the Prey series is going to go forever. Right now, he plans to end it (in its current incarnation) in two years. He says that he may still write Lucas novels in the future, but they won't have the Prey title on them. So while he won't be killing Lucas, he'll be killing the naming scheme.
That's the plan, anyway.

Why does he use a pseudonym?
Because the publication dates of The Fool's Run and Rules of Prey were too close together (Rules of Prey was slated for July of 1989, and The Fool's Run was going to come out the following September). Now, it's considered poor form to have two debut novels released in the space of that short a time, or even to have two debut novels period. Since The Fool's Run had already been sold under the name John Camp, a pseudonym had to be used for the other book (because Putnam didn't want Henry Holt riding on the publicity for Rules of Prey).

So where did "Sandford" come from?
Sandford is his paternal grandmother's maiden name. Sometimes he'll say that he's named after his great-grandfather Sandford. While that's true, it still leaves four possibilities. I'm just narrowing it down to one by phrasing it the way I do.

Has he written any children's books?
No, he hasn't written any children's books, nor has he illustrated any. There is, however, a writer/illustrator named John Sandford who writes primarily children's books. He is not in any way related to this author.

Has he written any Christian philosophy / inspiration books?
No, but there are two writers with similar names who write on that topic and the names get confused with the Prey series author.
One is John Loren Sandford, founder of Elijah House. He (along with his wife) has written more than two dozen books on Christian philosophy and spirituality. The Elijah House website is at http://www.elijahhouse.org/. He has not written any crime thrillers.
The other is John A. Sanford, Jungian psychoanalyst and Episcopal priest (according to this article on WikiPedia. He died in 2005.

Why is the website a .org instead of a .com?
Because johnsandford.com was already taken when I tried to get the domain. It had been registered by domain squatters — no surprise there — but these people were playing the "noble" card. See, they claimed that their company existed solely to register celebrity names and hold them until the "rightful" celebrity shows up to take it away, at which point they'd give it away for free. This would prevent the name being used for porn sites. As I said, noble.
Alas, it turned out that what they were really doing was using their ownership of the site to leverage themselves into a different job: that of running the site for the celebrity in question. When I was adamant that, no, I was the webmaster and I wanted the name, they offered to turn it over for free. Plus about $700 in shipping and handling.
I could have done it, sure. I could have paid $700 to domain squatters and gotten the name. I could also have taken them to court, since a court had recently ruled that for personal names, if you don't have a reasonable claim to that name, you can't hold the domain name from someone who does have a reasonable claim. But the easier path by far was to just get .org. Since I already had a .org (for something completely different) and since the Sandford site wasn't meant for profit, I went with that solution.
They eventually sold the domain name (or lost it, perhaps) and now it's a series of meta-forwards to a generic geo-targeted advertising page. Since this website's comfortably been a .org for more than a decade, I've got no particular desire to try to get the .com.
And that's the end of that. Now you know.