As both Hot Licks and choster say (in comments above), a "hype job" is simply a production, promotion, or other undertaking characterized by hype. The emphasis is on hype, and it is an unusual word.
Merriam-Webster's Eleventh Collegiate Dictionary (2003) presents five separate entries for hype, and is noncommittal about the word's origin in all but one of the five cases:
hype n [by shortening and alter. fr. hypodermic] (1924) 1 slang : a narcotics addict 2 slang : HYPODERMIC
hype vt hyped; hyping (1938) 1 : STIMULATE, ENLIVEN‚ usu. used with up {hyping herself up for the game} 2 : INCREASE
hype vt hyped; hyping [origin unknown] (ca. 1931) 1 : PUT ON , DECEIVE 2 : to promote or publicize extravagantly {hyping this fall's TV lineup}
hype n (1955) DECEPTION, PUT-ON 2 : PUBLICITY; esp : promotional publicity of an extravagant or contrived kind {all the hype before the boxing match}
hype adj. (1989) slang : EXCELLENT, COOL
In the early 1970s, when I first encountered hype being used in the sense of promotional buildup, I thought that the term was simply a shortening of hyperbole (which MW traces to the fifteenth century with the meaning "extravagant exaggeration"). But slang dictionaries differ on this point.
From Harold Wentworth and Stuart Flexner, Dictionary of American Slang (1961):
hyped-up adj. Artificial, phony, as though produced by a hypodermic injection of a stimulant. {Citation from 1950 omitted.] See hopped-up [which the dictionary defines as "Under the influence of narcotics; drugged").
Robert Chapman & Barbara Kipfer, Dictionary of American Slang, third edition (1994) has this:
hype 1 v by 1937 To blatantly promote [citations omitted] 2 n Advertising or promotion, esp of a blatant sort [citation omitted] 3 v by 1914 To trick; deceive; originally, to short-change 4 v by 1938 =HYPE UP {origin unknown, perhaps related to hyper, "hustle," of obscure origin, found from the mid-1800s; recent advertising and public relations senses probably influenced by hype [in the sense of "hypodermic needle"] as suggesting supernormal energy, excitement, etc, and by hyper and hyperbole; sense 4 supported by a 1914 glossary: "Hyper, current among money-changer. A flim-flammer"}
In the quotation from the Washington Post, "hype job" carries the idea of being mostly or entirely fluff or hot air emitted for the purpose of ringing up sales for an undeserving book. Interestingly, the word job in this instance refers to the book (in much the same way as the word job in "hatchet job" refers to a hostile review or exposé), and not to the job of producing the "hype job" (or in the corresponding example, the "hatchet job") nor to the person or persons who took on that job.