Walter Mosley is one of the most celebrated writers in the genre, and since 1990's Devil in a Blue Dress, his Easy Rawlins books have been favorites. Easy is part of a sub-tradition of what we might call 'reluctant detectives.' He isn't a licensed PI, just a guy people turn to for help. Fans thought the series might be over when Easy drove off a cliff in Blonde Faith in 2008, but he's back, in Little Green, on the Sunset Strip, in the southern parts of town, and out by the beach during the flower-power 1960's.
Dan Fante's Point Doom is a real thriller, with Girl with the Dragon Tattoo-level violence and splatter, maybe even more. Many detectives in the genre are defrocked cops; Fante one-ups that and makes his protagonist, who bears a not-superficial resemblance to Fante himself, an ex-private investigator who has drunk his way out of his license. Now sober, he refuses to get pushed around, and lots of people try. (Fante's last book was a memoir of his father, the legendary John Fante.)
Steph Cha is the newcomer, and her Follow Me Home features a Korean-American heroine, Juniper Song, who has a Raymond Chandler fixation, a "What Would Philip Marlowe Do?" approach to life. For lovers of the city, this is a treat, with visits to a dozen different recognizable neighborhoods, across the ethnic enclaves and the enclaves of the rich, with a fun, spunky narrator with real depth, and a true noir plot: people are lousy, and then they disappoint you -- except maybe Cha and Song.