Here is a book I never got round to buying until recently and so I briefly review it here and will add it to the Nessie bibliography.
Joe Zarzynski was active in the search for The Loch Ness and Lake Champlain Monsters in the 1970s and 1980s. He made various trips to Loch Ness but his main focus was on his local cryptid, "Champ" on which he wrote the 1984 book "Champ - Beyond the Legend". Below is a picture of him (right) with famous monster hunter, Tim Dinsdale.
In 1986, he wrote this book which combined two of his major interests, lake cryptids and underwater archaeology. At 111 pages, it is an afternoon read with about 60% of the book devoted to Loch Ness, so it qualifies for the book list. However, the book is not just about underwater wreckage.
The subjects covered in the book from a Loch Ness point of view are the Zulu-class boat wreck of Temple Pier, John Cobb's "Crusader" boat, the Wellington Bomber, the Sherlock Holmes monster, and the 1930s Steam Engine. Non "wreckage" items include the Goodyear Blimp, Ken Wallis' autogyro, submarines and atmospheric diving suits, Nessie boat collisions, giant nets and so on.
One thing I noted was the reference to the Zulu-class boat and I recalled a recent article on divers at Loch Ness which included a reference to a Zulu-class wreck, but off Foyers on the other side of the loch and discovered much later in 2002. Also, since the book was written, parts of John Cobb's boat have been located. Doubtless, other wrecks lie across the bottom and sides of Loch Ness and most likely a number of Nessie carcasses.
Since those days, Joe has left the cryptozoological field and has pursued his other love of investigating shipwrecks. You can find an example of that here. He still supports cryptozoology and believes there is something to the Champ phenomemon.