This 1972 novel by American author Hunter S. Thompson is one of the books that Jess brought to Stars Hollow with him, seen strewn around the bedroom he shares with Luke.
The book is autobiographical, based on two trips to Las Vegas Hunter S. Thompson took with attorney and political activist Oscar Zeta Acosta (called Dr. Gonzo in the novel) in 1971. In the novel, the characters descend on Las Vegas to chase the American dream in a drug-induced haze, ruminating on the failure of the 1960s counterculture. First published in Rolling Stone, the book is Thompson’s most famous work, and his subjective blend of fact and fiction became known as “gonzo” journalism.
It’s notable that this is another autobiographical novel about travel and the American dream that Jess has brought with him, and the “fear and loathing” a comment about how he feels being dumped on a relative in a small town. Which is interesting, because it means Jess not only hates Stars Hollow, he’s scared by it, and a lot of his sneering and posturing are an attempt to disguise that.
I think we’re meant to be impressed that Jess is reading a book by a journalist, as if to say, “Jess is not only smart and enjoys reading, like Rory, but he’s interested in journalism, like Rory”. Unfortunately the writers already made Dean a fan of Hunter S. Thompson (back in the days when Dean read books and understood films), and he introduced Rory to Thompson. This undercuts Jess’ intellectual status quite a lot, although it does show he and Dean may be more alike than it appears at first sight.