Cover Illustration by Barbara Remington (lion cover)
Five printings, August - December 1965.  These impressions have second edition (1951) text.  Tolkien disliked the art generally, and had a particular objection to the lion on the cover, as there is no lion in the story.  This edition predates the use of ISBNs, but the publisher book number does sometimes come up in keyword searches.  RRP $.95

Cover Illustration by Barbara Remington
The first 1966 printing (the 6th U.S. paperback printing overall) gives a first printing statement, but it also gives the complete publishing history and is labeled "revised edition".    The lion has been airbrushed out.  Some copies have the title in green, and it is often seen in aqua - the ink used for aqua printings may have been prone to fading.  This was given an ISBN in 1970, and these can sometimes be found using it, though the complete number is printed nowhere in the book.  There were 41 printings in this cover.  RRP $.95

Cover Illustration by J.R.R. Tolkien
Each year between 1973 and 1977, this was given a new ISBN and a price increase.  From this point on, matching Ballantine or Del Rey MMPBs are included in the Tolkien Box Set.  These are hard to find in collectible condition, but there are quite a few decent reading copies on the market.  About 34 printings in this cover.  RRP $1.25 - $2.50

Features imagery from the animated film by Arthur Rankin, Jr. and Jules Bass.  These are known for breaking just from readers thinking about opening them.  RRP $8.95

Houghton Mifflin.  It is unclear whether this was sold separately from the 1978 green boxed set.  Based solely on availability I would guess not;  then again, you don't see too many green sets either.  Either way, any that are running around loose in the used book market bear the same ISBN as the 1988 TPB edition, so get a good description...

Cover Illustration by Darrell K. Sweet
The Special Silver Jubilee Edition, celebrating The Lord of the Rings 25th anniversary.  The text was revised and printing number started over with one(1) in January 1982.  First 1982 printings describe the Tolkien art cover on the copyright page, the second does not, some later ones do.  Very sketchy.  Black title on yellow until 1984, when it became white on more of a goldenrod, and the ISBN changed.  At least 14 printings in this cover.  RRP $2.50 - $2.95

Cover Illustration by Darrell K. Sweet
The cover art and design are the same, this is a variant of the 1981 edition.  The 1985 covers (no Silver Jubilee announcement on the back) are darker, and almost metallic - something like a dull bronze.  Should I ever find one that does NOT claim to be a July printing, it might lend insight into how many runs were printed.  It could be two (the number of these on the used market seems a lot for just two), four is just as likely, more possible.  Ballantine got the copyright page wrong more often than right in the mid-late 80's.  RRP $3.95

Cover Illustration by J.R.R. Tolkien
Apparently four printings, July 1986 - July 1987.  There may have been more (or less), but it wouldn't be many, as The Lord of the Rings books in matching covers span these dates exactly.  A photo or exact published date is needed to track this cover down, because this ISBN is common to all Ballantine printings after 1986.  RRP $3.95

Houghton Mifflin,  DUST JACKET Illustration by Alan Lee
These were sold separately from the boxed set in lightly laminated dust jackets which had Lee illustrations on the front.  The 1992 issues have a Tolkien Centenary logo on the back of the jacket.  The copies that came with boxed sets had no jackets (the art was on the box).  Where stock photos are used, you will find that most descriptions say "different cover".  These either have no jacket, or it's a 1979 TPB.  RRP $7.95 - $11.95

Cover Illustration by Michael Herring.  This was used for the 50th Hobbit Anniversary cover, distinguished by a big round "50th Anniversary" statement on the front (not shown, but you can't miss it).  It was still there in 1990 after 10 printings.  This was the current cover for 11 years, and if Ballantine is to be believed (O don't take me there, lol), it may have been printed 70+ times in this cover.  RRP $4.95 - $6.99

Cover Illustration by J.R.R. Tolkien.
This contains the same text, illustrations, and forward by Christopher Tolkien as the 1987 gold 50th anniversary slipcased Collector's Edition.  QPB is not credited on the copyright page or anywhere else.  Because it shares an ISBN with all Collector's Editions, it can be very hard to locate.  RRP unknown.

Houghton Mifflin, Illustrated by Michael Hague
New wrinkle... some internet markets are reporting the publisher as Clarion and/or Mariner, and/or the date as 1997, and this apparently after it had been out of print for some years.  Mystifying.  It was in print for over 20 years, so you might still find new or like new copies for sale in odd corners, but so far as I know, it is out of print still (again?).
  RRP $12.95 - $17.95

Cover Illustration by Alan Lee.  Nice cover, sub-standard paper quality.  RRP  $12.00

Mass Market Paperback.  Cover Illustration by Ted Nasmith
There were only several printings of this cover design.  The art is incorrectly attributed to Michael Herring on the copyright page in the first few printings, though correctly attributed on the rear cover.  Upcoming LotR Motion Pictures are announced on the rear cover on late printings.  RRP $6.99

Cover Illustration by Ted Nasmith
The cover was updated for the boxed set when the LotR film art covers came out.  RRP $7.99 - $8.99

Trade Paperback, Cover Illustration by Peter Sis

Nice cover design with illustration by J.R.R. Tolkien.  The young adult edition is better quality for the same price.  RRP  $10.00 - $10.99

Available new,  RRP  $13.95

Trade Paperback.  Again, nice cover, but I am steering clear of Mariner Books editions - they'll be publishing on newsprint next.  RRP  $13.95

Available new,  RRP  $13.95

Available new,  RRP  $13.95