Cannery Row by John Steinbeck (1945) is the essential Monterey book — a loose collection of episodes set on the sardine-canning street, following the marine biologist Doc (based on Ed Ricketts) and the assortment of bums and dreamers who live nearby. It is shorter and gentler than Steinbeck's major novels, closer to a prose poem about a place and a moment than a plot-driven story. Walking the row after reading it, you can still see the bones of what he described.
Sweet Thursday by John Steinbeck (1954) is the sequel, set after the sardines have gone and the Row has changed. Less celebrated than the original but worth reading in sequence if you want to understand what the town felt it had lost.
Ed Ricketts: From Cannery Row to Sitka, Alaska edited by Katharine Anderson and others — a collection of writings by and about the real "Doc," the marine biologist Edward Ricketts, who ran Pacific Biological Laboratories on Cannery Row and was the intellectual centre of Steinbeck's circle. Ricketts' own ecological thinking, developed through his research in Monterey Bay, was genuinely ahead of its time.
The Log from the Sea of Cortez by John Steinbeck (1951) documents a six-week collecting expedition that Steinbeck and Ricketts made together in 1940 to catalogue marine life in the Gulf of California. The science is real, the friendship on the page is real, and the book reveals more about the Monterey intellectual world — the bar conversations, the ideas — than either Cannery Row novel.
Cannery Row: The History of Old Ocean View Avenue by Tom Hughes is a local history that fills in the documentary record: the Filipino and Chinese workers who actually did most of the canning labour, the corporate owners, the rise and collapse of the sardine industry. Essential background if Steinbeck's romanticised version leaves you wanting the harder facts.